Clinton doesn’t have to win a majority of white voters without a college education—Obama never did, after all. Even during the height of his 2008 campaign, he won just 40 percent of them. Four years later, his share slipped to 36 percent.

But in 2014, the bottom fell out, and it fell out in places where Democrats have performed relatively well with working-class white voters, even recently. The party didn’t just lose the white, working-class vote in places like Arkansas and West Virginia, where it has long since stopped being competitive at a presidential level. It also lost the vote in Iowa.

Braley, the Democratic Senate nominee in Iowa, won just 41 percent of the white, working-class vote in an overwhelmingly white state, exit polls showed, on his way to a stunning 9-point defeat in an open-seat race. Precise data was unavailable for Obama’s performance among the same group in Iowa in 2012, when he won the state comfortably, but he won 52 percent of voters without a college degree that year.

Other states showed a particularly weak performance among blue-collar whites: In Colorado, Udall got just 34 percent of their vote, to his opponent’s 61 percent. For Democratic presidential candidates, most plausible paths to the White House run through winning both of those states.