Forget Kentucky and Virginia, the worst election news for Republicans came out of suburban Pennsylvania

Reuters

President Donald Trump holds a campaign rally in Lexington, Kentucky

• Republican losses on Tuesday in Kentucky and Virginia are making headlines, but President Donald Trump should be more worried about the election results in the suburbs of Pennsylvania. 
• Pennsylvania is a key swing state that went for Trump in 2016 and will be a central battleground state in 2020.
• Democrats flipped suburban Delaware County, which has been controlled by Republicans since the Civil War, among other key wins in the previously Republican-dominated suburbs. 
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There's much discussion of the Republican Party's high-profile losses on Tuesday in Kentucky and Virginia, but historic GOP losses in Pennsylvania might be more concerning for the party in 2020.

Democrat Andy Beshear, Kentucky's attorney general, beat out incumbent GOP Gov. Matt Bevin, and Virginia Democrats took control of both state legislative chambers.

Beshear's victory had much to do with Bevin's status as one of the most unpopular governors in the country (Republicans swept other Kentucky state-wide races), and Virginia's blue wave was a long time coming. Neither state will be a battleground in 2020. 

But in Pennsylvania, Republicans suffered more surprising - and potentially consequential - losses. 

Democrats flipped suburban Delaware County, which has been controlled by Republicans since the Civil War. The county's five-member council, which was filled entirely by Republicans a few years ago, will now be occupied entirely by Democrats. 

In Chester County, Democrats took control of the Board of Commissioners and pushed out the Republican district attorney for the first time ever. Democrats also took the majority of the Bucks County Board of Commissioners. 

And in Philadelphia, a third-party candidate from the Working Families Party won a seat on the City Council reserved for the minority party. It had been held by a Republican for the last 70 years.  

"We broke the GOP," Brooks said at an election night party, according to the Philadelphia Inquirer. "We beat the Democratic establishment ... They said a black single mom from North Philly wasn't the right person but we have shown them that we are bigger than them."

Pennsylvania is a key swing state that went for President Donald Trump in 2016 and will be a central battleground state in 2020. Trump won the state by less than one percentage point - or about 44,000 votes of the more than six million cast - handing him Pennsylvania's 20 electoral college votes. 

Recent polling from The New York Times and Siena College showed former Vice President Joe Biden beating Trump in a general election race in Pennsylvania by three points, Sen. Bernie Sanders ahead of Trump by one point, and Sen. Elizabeth Warren even with the president. 

Democrats fear that Trump could lose the popular vote by a significant margin again, but prevail in the Electoral College, if an assortment of purple states swing in his favor in 2020. 

The suburban vote is also a point of serious concern for the Republican Party. Democrats are looking to zero in on these voters - many of them women, moderates, and more affluent college-educated voters who went for Trump in 2016. 

"Republican support in the suburbs has basically collapsed under Trump," Republican strategist Alex Conant told the Associated Press on Wednesday. "Somehow, we need to find a way to regain our suburban support over the next year."

The trend in Virginia, where Democrats have surged in the northern part of the state and in the Richmond suburbs, also bodes poorly for Republicans, even in right-leaning suburbs.