There are some key districts to watch as the returns roll in on Nov. 6:
First and foremost, the 23 seats that re-elected their Republican congressman in 2016 but pulled the lever for Democrat Hillary Clinton for president. That segment includes districts in historically ruby red Orange County, Calif., such as the 45th District held by Rep. Mimi Walters and the 39th District, where House Foreign Affairs Chairman Ed Royce chose to retire rather than run for re-election.
Next up are some of the Republicans’ untested conservatives — those incumbents running for re-election in districts gerrymandered to protect GOP candidates which could flip because the Democrat is a better politician and has attracted more resources. Rep. Dave Brat (R-Va.), running in the Richmond suburbs, is among them; so is Rep. John Culberson (R-Texas), facing his toughest general election challenge ever in the suburbs of Houston.