These 25 Congressional races to watch are some of the most competitive in the 2018 midterm elections

Maine's 2nd congressional district

The incumbent: Republican Rep. Bruce Poliquin is serving his 2nd term representing the district. While not as much of staunch Trump ally as other vulnerable incumbents, Poliquin faced backlash over his votes on healthcare and the GOP tax bill, and his reported inaccessibility to his constituents.

The challenger: The Democratic nominee is Maine state representative and majority whip Jared Golden. He's a Marine Corps veteran who's served in Iraq and Afghanistan and former staffer for Sen. Susan Collins, who touts his record of passing bills to help union workers in the legislature.

An Oct. 15-18th New York Times/Siena College poll shows Poliquin and Golden neck-and-neck, with 41% of those polled indicating support for Poliquin and 41% for Golden.

The lay of the land: The largest congressional district east of the Mississippi River, Maine's 2nd district encompasses 80% of the state. It's largely rural and working-class, with a tradition of strong organized labor.

One Bangor Daily News article describes it as a "fiercely libertarian district historically willing to throw its weight behind individual candidates rather than political parties."

Partisan dynamics: The 2nd district's Cook Political Voting Index (PVI) is R+2, meaning it's two points more Republican than the rest of the country, on average. While Democrats have a very slim registration advantage, the district voted for Trump in 2016 by a margin of seven percentage points, 51% to 44%.

Ratings and predictions: FiveThirtyEight's forecast rates the race as a toss-up, giving Golden a 3 in 5 chance of winning.

What the local experts say: Michael Sherman, a politics reporter who has been covering the race for the Bangor Daily News, told Business Insider in an email that Golden's success will likely be reliant on how much he's able to tack Poliquin to Trump.

"For me, the environment is the key thing to watch. The polling that I've seen seems to consistently suggest that Trump is more popular there than he is in the US and Maine overall," wrote Sherman.

"Poliquin has contorted himself to avoid talking about Trump in the past and that may continue, but I don't think Trump is a drag for him here like he is for other Republicans in suburban areas," said Sherman. "I'd be cautious in thinking that even a 'blue wave' would necessarily oust Poliquin."

Sherman noted, however, that the presence of two liberal unaffiliated candidates in the race could marginally benefit Golden by siphoning votes away from Poliquin in Maine's recently-introduced ranked-choice voting system.

Florida's 26th district

The incumbent: Rep. Carlos Curbelo, currently serving his 2nd term, is a rare moderate Republican in the House.

He's notably crossed the aisle on issues including abortion, climate change, and government spending, but he also voted to repeal to the ACA and to approve the Trump tax bill.

The challenger: Democratic nominee Debbie Mucarsel-Powell is a native of South Florida who has spent most of her career working in local nonprofits. Like Curbelo, she hails from a first-generation immigrant background.

The lay of the land: The 26th district is comprised of the southernmost tip of Florida, and includes the popular vacation destinations of the Florida Keys and Everglades National Park. It's almost 80% Hispanic, with a sizeable population of Cuban immigrants.

Partisan dynamics: The 26th's district's Cook political rating is D+6, making it the most Democratic district to be represented by a Republican in the country. The district went for Hillary Clinton by a 16-point margin over Donald Trump in 2016.

Ratings and predictions FiveThirtyEight rates the race as a pure tossup, giving each a 1 in 2 chance of winning. An October 19-24 Siena College/New York Times poll shows Mucrasel-Powell leading Curbelo by just one point.

What the local experts say: Ryan Nicol, who covers South Florida for FloridaPolitics.com, told Business Insider that given Curbelo's bipartisan record, he's not so sure that Democrats can successfully paint him as a Trump surrogate.

"A big sticking point in this race is whether the Democrats can make [Curbelo] seem not-so-moderate," he said.

But Nicol wasn't positive that the Democrats' best efforts would be necessarily enough to unseat Curbelo — even if they win back the House.

"If the Democrats are struggling to win the House, I could see Curbelo getting upset, it's possible," he said. "But even if the Democrats do moderately well, I could still see Curbelo hanging on."

Iowa's 3rd congressional district

The incumbent: Rep. David Young, a former staffer for Sen. Chuck Grassley, is serving his 2nd term in office. He had an unusual path to Congress, in which a Republican convention selected him to be the nominee in 2014 after he received only 35% of the vote in a crowded primary.

Young has been playing defense by distancing himself from the Trump administration's controversial agricultural tariffs that have adversely affected Iowa corn and soybean farmers.

The challenger: The democratic nominee is Cindy Axne, a small-business owner and former Iowa state official who led a successful effort to make all-day kindergarten available to every student in the West Des Moines public school system.

The lay of the land: The 3rd district covers a chunk of Southwestern Iowa, including the capital city of Des Moines. It's over 90% white.

Partisan dynamic: The 3rd district's Cook partisan lean is R+1. Trump carried the district by just 4 percentage points over Hillary Clinton in 2016.

Ratings and predictions: FiveThirtyEight rates the race as 'lean Democratic', giving Axne a 5 in 8 chance of winning. An October 25-27 poll from Siena College/The New York Times has Axne leading Young by 2 points.

What the local experts say: Steffen Schmidt, a professor of political science at Iowa State University, told Business Insider that the registration dynamics give neither political party a clear majority, meaning that both sides will need to court unaffiliated voters.

"Neither party has enough voters without getting a good chunk of the independent voters and also 'poaching' some members of the other party," he said.

"Democrats and Axne will need a big turnout by Democrats in the Third, a few old school, moderate Republicans, and then enough independents to cross the finish line."

Dennis Goldford, a professor of political science at Drake University, told Business Insider in a phone call that even though Trump looms large, Axne and other democrats in Iowa should stick with the issues that hit close to home.

Goldford said Axne and other will be more successful in courting the voters they need by focusing on the "bread-and-butter issues" such as jobs and infrastructure, as opposed to running the risk of alienating voters by making the race revolve around a "polarizing" figure such as Trump.

Texas' 23rd congressional district

The incumbent: Rep. Will Hurd is a former CIA covert officer serving his 2nd term in Congress, where he, like Rep. Curbelo in Florida, has developed a reputation as a relatively moderate Republican willing to cross the aisle, despite his mostly conservative voting record.

Hurd spoke out against the Trump administration's family separation policy, and penned a powerful op-ed in the New York Times in which he accused Trump of being "manipulated by Russian intelligence" after his controversial summit with President Vladimir Putin.

The challenger: Democrat Gina Ortiz-Jones is a dynamic former Air Force intelligence officer, Obama administration official. If elected, she would be the first Filipina in Congress and the first woman, Iraq War veteran, and openly LGBT+ person to represent the 23rd district.

The lay of the land: The largely rural district occupies a giant swath of land in South Texas that stretches from San Antonio to outside El Paso, and contains over 800 miles of the US-Mexico border. Almost 70% of its residents identify as Latino.

Partisan lean: It's Cook Partisan Lean is R+1, but Hillary Clinton won the district by 3 points in 2016. The 23rd is a true "swing district," having alternated between Democratic and Republican control many times in the past few decades.

Ratings and predictions: While the race was considered very close for most of the election cycle, FiveThirtyEight now rates it as likely Republican. An October 13-18 Siena College/New York Times poll gives Hurd a comfortable 15-point lead – but anything could change ahead of election day.

What the local experts say: Bill Lambercht, who covers the race for the San Antonio Express-News, told Business Insider the national environment will likely play a large role in how the race shakes out.

"So many congressional races are going to hinge on how people view this administration," Lamberht said.

"I think Hurd, by criticizing, Trump in strong terms and going down to the border to view a detention camp during the height of the family separation crisis, has probably been able to diminish that anti-administration energy that's been so strong."

Lambercht added that besides her strong fundraising performance thus far, Ortiz-Jones' military background could give her an edge in the 23rd district, which is home to two air force bases.

California's 48th congressional district

The incumbent: Republican Rep. Dana Rohrabacher has represented Orange County in Congress since 1989, previously the Congressman for the 46th district before it was redistricted to become the 48th.

Dubbed "Putin's favorite congressman" by his critics, Rohrabacher has recently been scrutinized by what some say are suspicious connections to Russia.

Rohrabacher, a close ally and supporter of Trump, has routinely advocated for closer US-Moscow relations and publicly defended Russia's annexation of Crimea, in addition to a number of their other actions in global conflicts.

The challenger: Democrat Harley Rouda is a local entrepreneur, attorney, and philanthropist who has not previously held elected office. He was a registered Republican who regularly donated to GOP candidates until very recently.

The lay of the land: The 48th district hugs hundreds of miles of pristine coastline in the wealthy Orange County, including the popular surfing destinations of Huntington Beach, Newport Beach, and Laguna Niguel.

Partisan dynamics: Orange County has traditionally been a reliable Republican stronghold with a R+4 Cook PVI, but the 48th district voted for Clinton by just two percentage points in 2016. Rates of Republican voter registration have been steadily declining, and the district has become more racially diverse over the past decade.

Ratings and polls: FiveThirtyEight rates the race in the 48th as 'lean Democratic,' giving Rouda a slim advantage. An October 17-21 Monmouth University poll shows Rouda trailing Rohrabacher by just 2 points.

What the local experts say:

Matt Coker, a senior staff writer for OC Weekly Magazine and author of the recurring column "Dana Watch" told Business Insider that based on his years of covering Rohrabacher, the changing partisan and demographic dynamics of the 48th district will likely not be enough to oust him — but Rouda's Republican background could help. "Whether his Democratic opponent has been super competent or a total nutcase, it really has not stopped Rohrabacher from cruising to victory," Coker said. "The one glimmer of hope I see for Democrats is that Harley Rouda is in the investment and real estate business and until very recently he was a Republican." "On paper and in photographs, he appears to be a country club Republican, just like most GOP voters in that district," Coker said of Rouda.

Utah's 4th congressional district

The incumbent: A relatively popular Republican incumbent from conservative Utah might not seem like an easy pick-up opportunity for Democrats, but incumbent Rep. Mia Love, the first-ever African-American Republican congresswoman and former Mayor of Saratoga Springs, is fighting to keep her seat.

While she won re-election in 2016, she's been embroiled in a number of campaign finance scandals, including having a complaint filed against her campaign with the Federal Election Commission for her campaign allegedly illegally raising money for a non-existent primary fight.

The challenger: Ben McAdams is the current Salt Lake County Mayor and attorney who previously practiced at the white shoe law firm Davis Polk and Hardwell before serving as a Utah State Senator from 2009-2013 and Salt Lake County Mayor. He's also worked as an adjunct law professor at the University of Utah.

The lay of the land: Utah's 4th district includes some of the suburbs of Salt Lake City and stretches south.

Partisan dynamics: The district, created after a 2010 redistricting, is rated R+13 by the Cook Political Report, but was represented by a Democrat from 2012 to 2014.

Ratings and polls: FiveThirtyEight's deluxe model rates the race as a toss-up. Two recent polls from the New York Times/Siena College and the University of Utah/Salt Lake Tribune place Love and McAdams in a dead heat, while an October 26 Dixie Strategies poll gives McAdams a 6-point lead.

What the local experts say: Jason Perry, director of the University of Utah's Hinckley Institute of Politics, told the Salt Lake Tribune in mid-October that recent polling indicates McAdams is successfully building Democratic support and poaching unaffiliated voters.

McAdams “needs to spend all of his time focusing on undecided Republicans and unaffiliated voters," Perry said. “Those two categories of voters remain open and up for grabs.”

Perry said that Love, however, needs to make sure her core base of voters turns out. "[Love] needs to be seen in all areas of her district. She needs to be seen knocking on those doors and telling people she wants and needs their vote," he said.

New Jersey's 3rd congressional district

The incumbent: Republican Rep. Tom MacArthur has served New Jersey's 3rd district in Congress since 2014 and is a reliable Trump ally, voting with the President 92% of the time.

MacArthur drew ire from some constituents earlier this year when he became the sole New Jersey representative to vote for the controversial GOP tax cut bill, and for introducing an amendment crucial to the Republican effort to repeal the Affordable Care Act in summer 2017.

The challenger: Andy Kim, the Democratic nominee, has stellar public service credentials. At the age of 36, he's earned a Rhodes Scholarship, served in the US Army as a strategic advisor to Gen. David Petraeus in Afghanistan, and directed Iraq initiatives for the National Security Council under President Obama.

The lay of the land: The 3rd district occupies a large, mainly suburban chunk of South Jersey.

Partisan dynamics: An R+2 district, New Jersey's 3rd went for Obama in 2008 and 2012, but Trump carried it by a 6-point margin in the 2016 election.

Ratings & predictions: FiveThirtyEight rates the race as a toss-up, giving Kim a 4 in 7 chance of winning. An October 21-25 New York Times/Siena College poll shows MacArthur with just a 1-point lead over Kim.

What the local experts say: Ben Dworkin, director of the Rowan Institute for Public Policy & Citizenship at Rowan University told WYNC in August that the sudden influx of cash into the race from the Congressional Leadership Fund, a conservative PAC, signals that MacArthur is in trouble.

"What's significant here is the Republicans have to spend money from a super PAC on a race that should have been not even competitive in the first place," Dworkin said.

And the South Jersey Record reports that Patrick Murray, the Monmouth pollster who conducted the July poll, believes the "findings follow the same pattern of other highly contested special elections this year, in which Democrats outperformed expectations in two staunch Republican districts that Trump carried in large numbers."

Kansas' 3rd congressional district

The incumbent: RepublicanRep. Kevin Yoder has represented the district for 4 terms in Congress, and is now fighting to hold onto his seat. While he tried to distance himself from Trump and the administration's controversial immigration policies in a debate with Davids, Trump endorsed him on Twitter just a few days later.

The challenger: Sharice Davids, 36, is an attorney and former MMA fighter who, if elected, would be one of the first Native-American women elected to Congress and the first openly LGBT congressperson to represent Kansas in Washington, drawing huge amounts of national attention to the race.

The lay of the land: The 3rd district is largely urban and suburban, almost entirely comprised of the suburbs of Kansas City. KCTV5 News describes it as a "mix of fast-growing bedroom communities, established suburbs, and city neighborhoods."

Partisan dynamics: Although the Cook Political Report gives the district a R+4 PVI, Hillary Clinton carried it by 1 point in 2016. Before Yoder took office, the district was represented by a Democrat for 11 years.

Ratings and predictions: FiveThirtyEight rates the race as likely D, giving Davids a 6 in 7 chance of winning. An October 14-17 New York Times/Siena College poll shows her leading Yoder by 9 points.

What the local experts say:

"You have voters that don't want Trump, you have voters who don't like what Yoder is, and Sharice Davids is the perfect antidote to all of that," Democratic strategist Jesse Ferguson told Business Insider in August.

"If you looked for the opposite of Trumpism and the opposite of Yoder's inside-the-beltway corruption, you would envision Sharice Davids," she said.

Patrick Miller, a political science professor at the University of Kansas, told Vox in August that the college-educated suburban voters who are disillusioned with Trump will be key to her victory--but playing to progressive identity politics could scare them away.

“There’s a danger in embracing at least the symbols, if not the policy, of progressive Democrats,” Miller told Vox. “That’s not the product that voters are looking to buy. It’s the flip side of the Rust Belt... whites with college degrees that cluster in suburbs are becoming more Democratic.”

New York's 19th district

The incumbent: Freshman Rep. John Faso is a longtime Republican figure who was a 2006 gubernatorial nominee, who casts himself as looking to serve interests along Conservative, Independence, and Reform party lines.

The challenger: Democratic nominee Antonio Delgado is an Ivy League-educated lawyer who draws frequent comparison to former President Barack Obama for crafting a message that includes his family and humble beginnings, attacks Faso for his vote last year to repeal the Affordable Care Act, and a message hopeful for progressive changes.

Delgado's past as a rapper has been a major talking point of Faso's campaign, which has identified lyrics touching on race and capitalism as "offensive."

Democrats, meanwhile, have attacked the Faso campaign and the Congressional Leadership Fund for what they see as deliberately racist and misleading ads focusing on Delgado's rap career rather than the issues facing the district.

The lay of the land: The 19th district includes the Hudson Valley and Catskills regions in the easternmost part of the state.

Partisan dynamics: The area has grown slightly more Democratic in the past few years, but the Cook Report lists its partisan lean as R+2.

Ratings & predictions: FiveThirtyEight rates the race as 'lean Democratic,' giving Delgado a 3 in 5 chance of winning. An October 24-28 Monmouth University poll showed Delgado leading Faso by 5 points.

What the local experts say: Laurel Elder, a political science professor at Hartwick College, told Business Insider Delgado's biggest obstacle would be garnering the community behind his challenge, but could benefit from voters wanting to go against the GOP.

"They’re very different candidates, and that’s one of the challenges Delgado faces without a doubt, getting his name out and getting people excited to come out and vote for him," Elder said. "Faso is a pretty well-known name... but it could be more that this vote is about Donald Trump."

Both campaigns have ramped up efforts on the ground to personally reach as many voters as possible for the tight race, Elder said.

"Not every year do the campaigns open headquarters in Oneonta, but this year both have," Elder said. "I think that shows the closeness of the race, as both have a good field operation that are more robust than I’ve seen in past years."

Virginia's 7th district

The incumbent: Republican Rep. David Brat has served Virginia's 7th since 2014, when the then-unknown economics professor delivered a shocking victory over former House majority leader, Eric Cantor, that was powered by Tea Party-oriented grassroots campaigning.

A member of the conservative House Freedom Caucus, Brat has stoked a movement within the historically Republican district, initially with his surprising win and later with a public comment last year complaining about women.

The challenger: Abigail Spanberger, a former CIA officer, is poised to make history, powered by the local group Liberal Women of Chesterfield County. With support from citizens still reeling from the 2016 election, she's outraised Brat by more than $140,000 in the second quarter.

The lay of the land: The 7th district stretches from the Richmond area to the exurbs outside Washington.

Partisan dynamics: In 2016, Trump carried the 7th, which the Cook Report cast as R+6. Democratic Governor Ralph Northam was the first Democrat to win in Chesterfield County since 1961, but lost the district by less than four points in 2017.

Ratings & predictions: FiveThirtyEight rates the race as a toss-up. An October 30-31 NYT/Siena College poll shows Brat leading Spanberger by 6 points.

What the local experts say: Alex Keena, an assistant professor of political science at Virginia Commonwealth University, told Virginia's WRIC Spanberger was posing an unusually tough challenge to an establishment incumbent.

"She's raised a lot of money. She has a lot of grassroots support -- but so does Brat," said Keena. "You don't really see that too often where the incumbent candidate and the challenger both have strong grassroots bases of support."

Texas' 7th district

The incumbent: Republican Rep. John Culberson has served the 7th since 2000, and is seeking a 10th term. Culberson is a longtime member of the Appropriations Committee and has weathered a few recent scandals, involving insider trading and spending campaign funds on Civil War memorabilia and fossils.

The challenger: Lizzie Pannill Fletcher was born and raised in the 7th, a 43-year-old lawyer who was inspired to run to take care of local concerns citizens didn't feel Culberson was addressing, though she has never previously held elected office.

The lay of the land: The 7th includes wealthy suburban neighborhoods west of Houston, and is home to George W. Bush and Sen. Ted Cruz.

Partisan dynamics: Since George H.W. Bush first turned the 7th red in 1966, he's had two successors. Mitt Romney won here by 21 points in 2012, and Clinton carried the district by a single point in 2016 following major demographic shifts in the district that have made it a realistic target for Democrats.

Ratings & polls: FiveThirtyEight rates the race as a toss-up. An October 19-25 NYT/Siena College poll shows Culberson leading Pannill Fletcher by just 1 point.

What the local experts say: "Any blue wave from Texas to Washington, including California, is going to start with this race," Democratic lobbyist Scott Eckart told The Atlantic. "If Culberson loses, I think all the others will follow."

Michigan's 8th congressional district

The incumbent: RepublicanRep. Mike Bishop has represented Michigan's 8th district in Congress since 2015. Before, he served as the majority leader of the Michigan State Senate and in the Michigan House of Representatives.

The challenger: Democrat Elissa Slotkin served three tours of duty in the Iraq War as a Middle East analyst for the CIA, and went on to serve on the national security staffs of Presidents George Bush and Barack Obama, as well as in policy roles at the Pentagon.

Bishop's campaign is attacking Slotkin for her significant out-of-state fundraising and her having lived most of her adult life outside Michigan.

The lay of the land: Michigan's 8th district stretches from suburban Oakland county to include parts of East Lansing.

Partisan dynamics: An R+4 district which Trump solidly carried by 7 points in 2016. While the Oakland County suburbs lean Republican, the western part of the district in East Lansing is decidedly more liberal.

Ratings and predictions: FiveThirtyEight rates the race as a toss-up, giving Slotkin a slim 5 in 9 chance of being re-elected. A September 28-October 3 NYT/Siena College poll gives Bishop a 3-point lead over Slotkin.

What the local experts say: Corwin Smidt, a professor of political science at nearby Michigan State University, told Business Insider that neither Bishop's national security background nor Bishop's incumbency advantage alone will be enough to sway voters, meaning it'll all come down to voter mobilization.

"Slotkin needs to turn out the Democratic voters that usually only vote in the general. Since we had record turnout in August, that's in reach," Smidt said. "Bishop needs to turn out or keep loyal the disaffected college-educated GOP voters in Oakland and Ingham who aren't pro-Trump."

Texas 32nd congressional district

The incumbent: Rep. Pete Sessions is a staunch conservative with long-standing connections to core Republican donors. He votes in line with Trump 97.8% of the time, according to FiveThirtyEight. Sessions won the Republican primary with a landslide 79% of the vote, but his alignment with Trump has caused friction with voters in the district Clinton won in 2016. Sessions also faced controversy when it was reported he took a secret trip to Venezuela to meet with President Nicolas Maduro.

The challenger: Democratic civil rights lawyer Colin Allred is a former professional football player and Obama administration alumnus, from whom he received an early endorsement. Running on a campaign that vocalizes support for voting rights, women's rights, improving public education, creating jobs, LGBT rights, gun violence prevention, and healthcare

The lay of the land: The district is in the northeast part of the state and includes Dallas.

Partisan dynamics: The 32nd district has an R+9 partisan lean, and is one of three Republican-held districts in Texas that Hillary Clinton carried in 2016.

Ratings & predictions: FiveThirtyEight casts the race as leaning Republican. The most recent poll from NYT/Siena College conducted Sept. 18-24 shows Sessions leading Allred by just one point.

What the local experts say: Mark Jones, a political scientist at Rice University’s Baker Institute, told the Dallas Morning News he wasn't as optimistic that the midterms will bring a shakeup.

"I think the Cook Report knows about as much about Texas politics as they know about barbecue, breakfast tacos, and the Bible, which is not much,” Jones said.

Jones said if voters are making their pick in accordance with their feelings on President Donald Trump, Sessions is likely safe. He said Cook’s prediction doesn't take voters' comfort within party lines in a district where Republicans have an average advantage of 12 to 15 points.

"They see it too much as a race of Allred and Sessions head-to-head, not as a team red, team blue race," Jones said.

Illinois' 6th congressional district

The incumbent: RepublicanRep. Peter Roskam has represented the district for over 10 years, serving as chief deputy minority whip under Eric Cantor and currently chairing the Subcommittee on Tax Policy on the powerful House Ways and Means Committee.

The challenger: First-time Democratic candidate Sean Casten — a scientist and clean energy executive — is giving Roskam his toughest re-election fight in years.

The lay of the land: The 6th district is located in the densely populated Chicago suburbs, and includes the city of Naperville. It's mostly white and relatively wealthy.

Partisan dynamics: Although the 6th district has a Cook PVI of R+2 and has been represented by a Republican since 1973, Hillary Clinton carrying the district by 7 points in 2016 could indicate it's getting more purple.

Ratings and polls: FiveThirtyEight designates the race as "lean Democratic," giving Casten a 5 in 8 chance of winning. An October 20-26 NYT/Siena College poll shows Casten leading Roskam by 2 points.

What the local experts say: Laurel-Harbridge Yong, a political scientist who studies congressional elections at nearby Northwestern University in Evanston, told Business Insider that Casten's moderate views and background in the private sector could make him an appealing choice to voters, but both candidates will need to position themselves as independent voices.

"Many suburban voters prefer conservative economic policies, but are turned off by Trump-esque rhetoric," she said. "This race then becomes a question of whether Casten is able to paint Roskam as a Trump puppet."

Harbridge added that Casten should "pull from the center and focus on people who voted for Trump but have misgivings now and want to find a way to signal that."

New York's 22nd district

The incumbent: First-term Republican Claudia Tenney has been a vocal Trump supporter in her remarks on the campaign trail and policy moves in Washington, also appearing with Trump and his daughter Ivanka at summer rallies and fundraisers.

Some analysts say Tenney's fervent support for Trump is alienating voters in key demographics, even though the 22nd has 30,000 more registered Republicans than Democrats.

The challenger: Democratic State Assemblyman Anthony Brindisi considered running in 2016 but is only now challenging his former Assembly colleague. Brindisi is a Utica native who served on the School Board and has bipartisan backing. He has a mix of credentials, from being a vocal critic of Democratic Gov. Andrew Cuomo to his top rating from the NRA.

The Cook Report identified Brindisi as one of approximately 60 Democrats who outraised conservative members of Congress, as he smashed his fundraising goals with no money from PACs.

The lay of the land: The 22nd encompasses a chunk of central New York, and includes the cities of Utica, Binghamton, and Cortland.

Partisan dynamics: President Donald Trump won 55 percent of the 2016 vote in the district, which the Cook Report rates as a R+6.

Ratings & predictions: FiveThirtyEight rates the race as a toss-up, with an October 15-18 Siena College poll showing Brindisi just one point ahead of Tenney.

What the local experts say: Utica College political science professor Luke Perry told local NPR affiliate WVRO that Tenney's "populist" approach could end up being a deterrent to voters.

"I think she looked at 2016 an election where she got less than 50 percent and Donald Trump did very well and outperformed her by the second-largest margin of any Republican," Perry said. "It seems that her approach in response to that is to try to be as much like the president as possible."

Perry said Brindisi's image may have wider appeal in the district, as "he’s positioning himself as someone who’s separate from corporations and not tainted by that influence and will help people in their day-to-day concerns like paying their bills."

Kentucky's 6th district

The incumbent: Republican Andy Barr was first elected in 2012, defeating an incumbent with a campaign that emphasized his priority of decreasing regulation in the coal industry.

Barr is a strong Trump echo in Congress, voting in line with him 96.7% of the time. Barr's campaign won the favor of the Congressional Leadership Fund, a top Republican super PAC that's focused on advertising spending in toss-up districts.

The challenger: Former Marine Corps pilot Amy McGrath has military and foreign affairs policy experience and is running a campaign that emphasizes issues surrounding healthcare, sexual harassment, medical marijuana, gun control, campaign finance, and climate change.

An ad released by McGrath went viral in early August as she took aim at Barr and Kentucky Sen. Mitch McConnell, zeroing in on her priorities for improved healthcare access.

The lay of the land: The 6th occupies a large portion of central Kentucky, including the city and suburbs of Lexington.

Partisan dynamics: The 6th's Cook Partisan Lean is R+9, and Donald Trump carried the district by 15 points.

Ratings & predictions: FiveThirtyEight rates the 6th as a true toss-up. A Sept. 6-8 Siena College poll has Barr leading by just one point, with 7% of voters undecided.

What the local experts say: Stephen Voss, a political science professor at the University of Kentucky, said McGrath's approach has positioned her to win over hostile or undecided voters.

"The most important thing Amy McGrath is doing is experimenting with a different approach for Democrats to make headway in conventionally Republican districts," Voss said. "She's campaigned ideologically as a fairly conventional Democrat taking liberal stances."

New Jersey's 7th district

The incumbent: Republican Leonard Lance has served five terms in New Jersey's 7th. Lance has worked to distance himself from the Trump administration and GOP, voting against the Republican tax bill and voting to repeal the Affordable Care Act.

However, he's still backed by the Republican super PAC the Congressional Leadership Fund, which recently launched an ad campaign praising his bipartisanship.

The challenger: Tom Malinowski is a former assistant secretary of state for democracy, human rights, and labor under former President Barack Obama and a top official at Human Rights Watch.

Malinowski earned attention in early September for releasing an ad that featured the recently deceased Sen. John McCain, with whom he worked on legislation to ban torture.

The lay of the land: The 7th occupies a large portion of north-central New Jersey.

Partisan dynamics: Mitt Romney won the district in 2012, but it was one of 23 Republican-held congressional districts to back Clinton in 2016 (49% to Trump's 48%). The Democratic Congressional Campaign Committee listed the district as a target in 2018.

Ratings & predictions: FiveThirtyEight rates the district as lean Democratic, giving Malinowski a 7 in 10 chance of winning. An October 28-31 NYT/Siena College poll gave Malinowski a 7-point lead over Lance.

What the local experts say: Montclair State political science professor Brigid Harrison told Business Insider that though the district appears to be a toss-up on paper, Lance's record and reliable voter demographics means he's looking at a likely win.

"Lance is one of the more moderate Republicans," Harrison said. "Though he has a very strong challenge in Malinowski, and despite what we hear about the blue wave, need to look at the district and recognize that there are registration advantage for Republicans."

Harrison described the 7th's typical voters as "well-educated, affluent, sophisticated, fiscally conservative, and socially liberal."

"My take is that this is not as competitive as people make it out to be," Harrison said.

Minnesota's 2nd district

The incumbent: Republican Jason Lewis was first elected in 2016 after a career as a radio show host and conservative commentator, which earned him comparisons to Trump for his bombastic media personality.

The challenger: Angie Craig currently works for healthcare company St. Jude Medical and has experience in health policy, media, government relations, and corporate communications. Though endorsed by former President Barack Obama, Craig narrowly lost to Lewis in 2016 by two points.

If elected, Craig would be Minnesota's first openly gay member of Congress.

The lay of the land: The 2nd occupies a large southeast chunk of the state, partially including the Twin Cities metro area.

Partisan dynamics: The 2nd backed Barack Obama in both terms, but voted for Trump in 2016.

Ratings & predictions: FiveThirtyEight currently rates the race as "likely D," giving Craig a 6 in 7 chance of winning. A September 28-October 2 poll showed her leading by a comfortable 12 points.

What the local experts say: Larry Jacobs, a political science professor at University of Minnesota's Humphrey School of Public Affairs, told Business Insider Lewis' brash reputation doesn't have a positive legacy among voters, but Craig's identity might not be strong enough to establish herself over him.

"As a radio host, he's known as acrimonious and controversial," Jacobs said. "Though he hasn't been in office long, he has a past that will cast a shadow over him in a district with more college-age voters and people of color that rightfully belongs in the toss-up category."

California's 45th congressional district

The incumbent: Rep. Mimi Walters, a former banker and California state legislator, is serving her 2nd term in Congress. Unlike other GOP incumbents running in tough races, she's tying herself closely to Trump, saying "he stands for what we stand for," earlier this year.

The challenger: Democratic nominee Katie Porter is a consumer protection attorney and law professor making her first run for office after a career taking on big banks and predatory lenders. She's endorsed by progressive leaders such as Elizabeth Warren and Kamala Harris and supports Medicare for all.

The lay of the land: The 45th district lies in Orange County, and includes the cities of Irvine and Anaheim Hills. Like California's 39th district, it's home to a sizeable and ever-growing immigrant community.

Partisan dynamics: The 45th district voted for Hillary Clinton by 5 points in 2016, but is rated R+3 by Cook.

Ratings and predictions: FiveThirtyEight rates the race as "lean Democratic," giving Porter a 5 in 8 chance of winning. A NYT/Siena College poll from October 26-31 shows Porter leading Walters by 2 points.

What the local experts say:

"Is Mimi Walters the most endangered GOP incumbent of 2018? Far from it. But due to the demographics of her district, the nature of her Democratic challengers and her own low-profile, pro-Trump orthodoxy, she may be the most typical — and telling," wrote Yahoo News West Coast correspondent Andrew Roman in March.

"If you’re searching for signs of a Democratic wave, watch Walters. It could start sweeping through her corner of California first," he said.

North Carolina's 9th district

Republican Rep. Robert Pittenger is the first House incumbent to lose his party's primary.

The Republican: Former pastor and staunch Republican Mark Harris lost to Pittenger by 134 votes in 2016, but defeated him in the primary to launch a campaign emphasizing tax reform, reduced federal spending, and a wall along the US-Mexico border.

The Democrat: Democratic candidate Dan McCready is a Marine Corps veteran and Harvard Business School graduate who won the party's 2016 primary.

The lay of the land: The 9th occupies a large part of south-central North Carolina along the border and includes a large Native American population, support which both candidates are hoping to secure.

Partisan dynamics: Cook rates the 9th as R+7, but the Trump-won district made the Democratic Congressional Campaign Committee's targets in 2018.

Ratings & predictions: FiveThirtyEight rates the race as a toss-up. An October 26-30 NYT/Siena College poll shows Harris leading McCready by just 1 point.

What the local experts say: Political scientist and Catawba College professor Michael Bitzer told the Charlotte Observer McCready is trying to "fit the district" in an area that's up for redrawing.

"There’s a history of Southern, conservative or moderate Democrats, just as there was a history of liberal Republicans in the Northeast," said Bitzer. "I think what McCready is trying to do is show there’s still room in the Democratic party... There’s still a sense of a middle that hasn’t been necessarily reflected, in both political parties."

Kansas' 2nd congressional district: open seat

Kansas' 2nd district, considered a safe Republican seat for decades, has been thrown into play by the retirement of incumbent Lynn Jenkins.

The Republican: Former US Army Airborne Ranger and federal defense contractor Steve Watkins seemingly came out of nowhere to win a crowded Republican primary with just 22% of the vote, largely due to hundreds of thousands of dollars poured into the race by his father.

Watkins was practically unknown to Republican leaders and voters before running for Congress and was criticized during the primary for taking meetings with Democratic party officials in 2017, living and voting outside Kansas for most of life, and not having a clear policy record to look to.

The Democrat: Paul Davis is an attorney by training who served five terms in the Kansas House of Representatives, including almost 10 years as minority leader. He narrowly lost in a run for the Governor of Kansas by 3.7 points in 2014.

Davis says he wants to use his record of bipartisanship and working across the aisle in the Kansas legislature to help reform Washington. He is one of many Democratic congressional candidates who have publicly rejected Nancy Pelosi's leadership.

The lay of the land: Kansas' 2nd district includes most of the Eastern part of the state, including the capital city of Topeka and the city of Leavenworth, home to a US Army base. The rest of the district is largely rural and agricultural.

Partisan dynamics: The 2nd district is one of the most solidly Republican of FiveThirtyEight's toss-ups. It has an R+10 partisan lean and was carried by Trump in the 2016 election by a whopping 19 points. It was, however, briefly represented by a Democrat from 2007 to 2009.

Ratings & predictions: FiveThirtyEight rates the race as a "toss-up," giving Davis a 5 in 9 chance of winning. An October 27-31 NYT/Siena College poll showed Davis leading Watkins by 4 points, 41% to 37%.

What the local experts say:

“[Watkins] has tied himself pretty closely to Trump. He’s trying very hard to appeal to that conservative base," Jim McLean, a politics reporter and editor at Kansas News Service, told KCUR in August.

"We shouldn’t forget that Trump won the 2nd district pretty handily in the 2016 presidential election," McLean said. "However, Paul Davis also won that district when he ran for governor in 2014, so it’s looks like it’s going to be a pretty interesting race.”

McLean said Davis' visibility and extensive record in Kansas politics combined with his his repudiation of Pelosi, a deeply unpopular figure among Republicans, could help him make up ground in such a solidly Republican district.

“His political profile as a moderate Democrat willing to work across the aisle might be appealing to voters in this district,” he said.

California's 39th congressional district: open seat

California's 39th congressional district was a Republican stronghold in Orange County for decades. But the retirement of long-time Republican Rep. Ed Royce combined with demographic shifts in the district has made the race a national target for Democrats.

The Republican: Young Kim is a former California state assemblywoman and longtime community relations aide to Royce who, if elected, would be the first-ever Korean-American to represent the Republican Party in the Congress.

Kim has been running as a moderate, locally-focused Republican, carefully taking on traditionally conservative positions while distancing herself from the Trump administration. She touts her decades of experience working in the community as reasons why voters should put their trust in her.

The Democrat: Philanthropist, education advocate, and Navy veteran Gil Cisneros will face Kim in November. He holds a nearly 5 to 1 fundraising advantage over Kim, partially due to self-funding his campaign with his multimillion-dollar fortune from previously winning the lottery.

The lay of the land: Parts of Los Angeles, Orange, and San Bernardino counties make up the largely suburban and highly diverse 39th district, which includes the communities of Fullerton, Yorba Linda, and Anaheim Hills.

The district has a sizeable immigrant population, with one-third of residents identifying as Latino and almost another third as Asian-American.

Partisan dynamics: The 39th district's PVI is exactly even, meaning it leans neither Democratic nor Republican. Hillary Clinton carried it by over 8 points in 2016, but it was won by Romney in 2012.

Ratings and predictions: FiveThirtyEight's deluxe model rates this race as a toss-up, giving Cisneros a slight 4 in 7 advantage over Kim. An October 18-23 NYT/Siena College poll shows Cisneros leading Kim by just one point.

What the local experts say: Fred Smoller, a political scientist at Chapman University, told the Orange County Register in August that he believes the race will come down to two main factors: whether Latino voters will turn out in large enough numbers for Cisneros, and whether Trump's high disapproval will drive enough Asian-Americans to split from the GOP, particularly younger ones.

“Trump is so unpopular among immigrant communities that you’re going to see some surprising results,” Smoller said of the race in the 39th.

“The threat the Latino community feels will encourage turnout. And I think a high number of younger Asians will turn out (for Democrats), as well," he said. "There seems to be a generational split.”

Minnesota's 1st district: open seat

Former Democratic Farmer-Labor Rep. Tim Walz left his position as the representative for Minnesota's 1st district to run for Governor, throwing the seat into play as a rare pick-up opportunity for Republicans.

The Republican: Jim Hagedorn has previously worked as a legislative assistant and a congressional liaison to the Financial Management Service and the Bureau of Engraving and Printing.

An op-ed in the conservative-leaning Washington Examiner described Hagedorn as the "worst midterm candidate in America" with the "political acumen of Rick Saccone and the misogynistic mind of Blake Farenthold" over some of his previous blog postings.

Hagedorn has called Democratic Sens. Maria Cantwell and Patty Murray "bimbos in tennis shoes" and propagated conspiracy theories about President Obama being born in Kenya, along with a host of other offensive remarks for which he has since apologized.

The Democrat: After serving two tours of duty during the Iraq War in the US army, Dan Feehan worked as a teacher and in the Obama administration as a White House fellow and assistant secretary of defense. Feehan is positioning himself as an independent voice for the district by rejecting corporate PAC money.

The lay of the land: The 1st district stretches across Southern Minnesota, bordering South Dakota to the West and Wisconsin to the East. It's largely rural and agricultural, but it's experiencing growth in it's biggest urban areas, Mankato and Rochester.

Partisan dyanmics: The district, rated R+5 by the Cook Political Report, voted for Obama by 2 points in 2012 but swung to vote for Trump by a stunning 15-point margin in 2016, making it a rare district to vote for Trump but re-elect a Democratic House representative.

Ratings and polls: FiveThirtyEight rates the race as a toss-up, with an October 16-20 SurveyUSA poll showing Feehan leading Hagedorn by just 2 points.

What the local experts say: Darrin Broton, a Democratic Farmer-Labor strategist in the 1st district told the Minnesota Post in late October that the race will come down to whether Feehan can both win back and turn out voters who picked Trump over Hillary in 2016: “The reason why Trump did so well, and why Walz almost lost, was the rural folk,” Broton said. “The question is, do those folks show back up this cycle?”

“A lot of those folks have a conservative bent to them, but they still have a big independent streak running through them," he added.

Washington's 8th congressional district

Rep. Dave Reichert is retiring after his seventh term, and has been a strong Trump ally in the historically Republican-held district, voting with Trump 92% of the time.

The Republican: Former State Sen. Dino Rossi is carrying Republican hopes to continue their hold on the 8th. The former real estate investor is well known across the state but has had three unsuccessful runs at higher office.

The Democrat: Pediatrician Kim Schrier has no prior campaign experience, but topped another Democratic candidate in the primary by less than one point to further her campaign, which champions health care reform.

The lay of the land: The 8th lies just east of Seattle and includes a mix of suburban, mountainous and rural communities.

Partisan dynamics: The Cook Report rates the race in the 8th as even, making for a true toss-up in the district that has never had a Democrat in the House, but is one of 25 Republican-held districts that backed Hillary Clinton in 2016 and earned a spot on the Democratic Congressional Committee's list of top midterms targets.

Ratings & predictions: FiveThirtyEight casts the 8th as "leans Democratic," giving Schrier a 5 in 8 chance of winning. An October 30-November 1 NYT/Siena College poll places Schrier and Rossi in a dead heat, with 45% of voters indicating an intent to vote for each.

What the local experts say: “This is as close to a coin toss race as you have nationally,” political consultant Ben Anderstone said of the race in the 8th district in a recent KING5 news interview.

Anderstone said the South Sound portion of the 8th district is "quite possibly is going to be where the race is decided" due to it steadily becoming more Republican as opposed to other parts of the district and having historically higher rates of voter turnout than other parts of the district that are becoming more Democratic.

New Mexico's 2nd congressional district: open seat

New Mexico's 2nd congressional district is one of the most solidly Republican seats in the southwest, but the retirement of Rep. Steve Pearce has made it a long-shot Democratic pickup opportunity. Now, outside cash is pouring into the district from both parties.

The Republican: State Rep. Yvette Herrell has served four terms in the New Mexico state legislature, and was one of the body's most conservative members. She is unabashedly pro-Trump, and has indicated she'll be a strong proponent of his agenda in Congress.

The Democrat: Xochitl Torres-Small is a water-rights attorney and former aide to Sen. Tom Udall. Torres-Small touts her experience helping bring universal broadband and cell service to rural residents in the 2nd district.

The lay of the land: One of the largest districts in the country, New Mexico's 2nd is comprised of the entire lower half of the state, including the cities of Las Cruces and Roswell, and vast swaths of oil country. The district also includes hundreds of miles of the US-Mexico border and is nearly 30% Hispanic.

Partisan dynamics: An R+6 district which Trump easily carried by 11 points in 2016.

Ratings and polls: FiveThirtyEight rates the race as a tossup, with an October 19-23 NYT/Siena College poll giving Herrell an 11-point lead over Torres-Small, but more recent polls showing a smaller margin.

What the local experts say: Brian Sanderoff, an Albuquerque-based pollster who conducted a poll of the district in early September, told the Las Cruces Sun-News that while Torres-Small is the best shot Democrats have had in years of taking over the seat, all the fundamentals of the district point in Herrell's favor.

"She's got an uphill battle because of the nature of the voting behavior in the district," he said of Torres-Small. "Even if Torres-Small wins Las Cruces by a larger margin than a typical Democrat, the question becomes: 'Can that offset the eastern part of the district?'"

Read more of Business Insider's 2018 Midterm Election coverage:

• All the dates, deadlines, and rules you need to know before voting in the 2018 midterm elections
• SENATE BATTLEGROUND MAP: The race for control of the Senate is as tight as it can be
• Here is the last day you can register to vote in every state
• Here are the deadlines in every state to vote absentee in the 2018 midterm elections
• You can take time off work to vote in 30 US states — but you're out of luck in the rest
• The evolution of American voting rights in 242 years shows how far we've come — and how far we still have to go