Candidates who SHOULDN'T try again:
Stewart Mills (MN-08)
Joe Garcia (FL-26)
Randy Perkins (FL-18)
Paul Babeau (AZ-01)
Matt Heinz (AZ-02)
Monica Vernon (IA-01)
Emilio Huerta (CA-21)
Danny Tarkanian (NV-03)
What's wrong with Matt Heinz (AZ-02)? He made it close.
Not really a rematch but Denise Juneau (D) should give it another go in Montana next year when it's an open seat and Zinke tries a run for senate. It's unfortunate that even though Bullock was reelected, Dems were wiped out of other statewide offices.
Also, maybe Myers (D) in NY-22, although her result wasn't all that impressive.