LIVE UPDATES: Follow the results of Pennsylvania's congressional primaries

• Pennsylvania is holding primaries in all 18 of its House of Representatives districts over the next week.
• There are notable Democratic primaries in Pennsylvania's first and 10th congressional districts and a crowded GOP primary in the 8th district.
• The state's governor issued an executive order allowing voters' mail-in ballots to be accepted through June 9 in Philadelphia and five additional counties, meaning results for several key races may not come in for several more days.

The stakes:

Pennsylvania is holding primaries in all 18 of its House of Representatives districts on Tuesday. This year's elections are the second round of House elections held under Pennsylvania's new House map, which the Pennsylvania Supreme Court ordered the state to redraw in 2018 after ruling the previous map was unconstitutionally gerrymandered.

There are notable Democratic primaries in two Republican-held districts likely to be competitive this fall. In Pennsylvania's 1st congressional district located in Bucks County, Christina Minello and Skyler Hurtz are facing off to compete against incumbent GOP Rep. Brian Fitzpatrick.

As the Philadelphia Inquirer noted, Fitzpatrick is one of just three Republican incumbents along with Rep. John Katko in New York's 24th congressional district and Rep. Mike Garcia in California's 25th district to be running for re-election in a district Hillary Clinton won in 2016.

In Pennsylvania's 10th congressional district, which includes the cities of Harrisburg and York, Pennsylvania's current Auditor General Eugene DePasquale and attorney Tom Brier are running in the Democratic primary to take on GOP Rep. Scott Perry. The Cook Political Report rates Perry's seat as a tossup district this year.

There's also a competitive Republican primary to face Democratic Rep. Matt Cartwright in Pennsylvania's eighth district located the northeast part of the state, which Trump carried in 2016.

Pennsylvania, which allows absentee voting without an excuse, will likely not report results from the first and tenth congressional district primaries, in addition to numerous other races, until next week.

After widespread reports of voters in highly populated counties not receiving their ballots in time, Governor Tom Wolf issued an executive order extending the deadline for voters in six counties — Philadelphia, Allegheny, Dauphin, Delaware, Erie, and Montgomery — to have their ballots counted. In those places, ballots will be accepted if they are postmarked by June 2 and arrive by 5 p.m. on June 9.

In the rest of the state, voters' absentee ballots must be received by 8 p.m. on Tuesday.