Washington (CNN) Key races in November's midterm election took shape Tuesday night, particularly in Pennsylvania, where Democrats see an opportunity to pick up several seats on their way to a potential House majority.

In the hotly contested Democratic primary for the Lehigh Valley House seat being vacated by retiring Republican Rep. Charlie Dent, former Allentown solicitor Susan Wild, who was backed by EMILY's List, claimed victory. The best known candidate in the race, Northampton County District Attorney John Morganelli, conceded to Wild. Morganelli was a target of progressives over his stances on abortion, illegal immigration and a series of now-deleted tweets that included praise for President Donald Trump.

In the new 1st District, Republican Rep. Brian Fitzpatrick -- one of the most endangered Republicans in this year's midterm elections -- survived a primary challenge and is now set to face Democrat Scott Wallace, a multimillionaire who has spent $2.5 million of his own money on the race. Wallace held off Rachel Reddick, an EMILY's List-endorsed 33-year-old former Navy prosecutor, to win the primary.

Democrats also picked Mary Gay Scanlon, a local school board member, in a packed primary in the 5th District, an area vacated by former GOP Rep. Patrick Meehan, where the Democrats are all but certain to make one of the 23 pickups they will need to take control of the House.

Rep. Lou Barletta won Pennsylvania's Republican Senate primary and is now set to take on Democratic Sen. Bob Casey in November. The race is one of 10 Democratic-held Senate seats on the ballot this fall in states President Donald Trump won in 2016.

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