(Charlie Archambault for USN&WR)
Control of the House could hinge on rematches in 10 races, all in districts currently represented by Democrats. Though the candidates are the same, the strategy in many races has flipped. Democrats nationalized the race last time, and the GOP is doing the same now, tying their opponents to House Speaker Nancy Pelosi and President Obama. The outcome of these races could decide who controls the House next year. Democrats, meanwhile, are hoping that some of the partisan arguments that won previously still have traction with voters. With Obama having won in most of these districts, the extent to which the Democrats can prevail again will be a measure of just how much American politics has shifted in recent years.