In an election this close — which, it should be noted, was actually a win for the Democrats under an honest popular-vote system rather than the anachronistic and indefensible Electoral College — many things made the difference. Voter suppression in Wisconsin might have been enough. FBI director James Comey’s eleventh-hour letter almost certainly was.

But something big seems to have happened, if exit polls are reliable (which is, you can’t say too many times, a big “if”): The parties swapped a chunk of their class constituencies.

More poor and lower-middle-class people voted Republican in this election than the last. More upper-middle-class and rich people voted Democrat. And union voters abandoned the Democrats dramatically.