Fewer Voters Are Crossing Party Lines

Straight-ticket voting has spiked:

Prior to 2010, 2002 was the only year in which the predictive power of past presidential results was over 40 percent. In other words, voters who favor Republican presidential candidates are now very likely to favor Republican Senate candidates. U.S. House and gubernatorial elections can be increasingly predicted by past presidential voting as well. The latter is especially interesting considering that governors are state, not federal, politicians.

The question going forward is whether the link between presidential and Senate results will increase, decrease or stay the same. If the straight-ticket effect doesn’t weaken, it could be bad news for Democrats, assuming we’re a 50-50 nation over the long haul. By our presidential vote metric, 54 Senate seats are in states that are more Republican-leaning than the nation on the presidential level, and 46 are in states that are more Democratic-leaning.