It would have been reasonable to expect, as I did, that “middle-class Joe” from Scranton, Pa., would show strength by winning back the white working-class voters who defected from the Democrats in 2016. If he could do so, he would rebuild the so-called blue wall of traditionally competitive states across the Midwest. Add to this the college-educated white voters whom Hillary Clinton won in 2016, and Mr. Biden would have a commanding lead.

But there is no sign that Mr. Biden has any special appeal to white voters without a degree in these states. Instead, he runs a bit ahead of Mrs. Clinton across the board, among college-educated and working-class white voters alike. (He led by an average of two points over Mr. Trump among registered voters across the six states.).

It seems that all but a sliver of the white voters without a degree who backed Mr. Trump in 2016 will stick by him in 2020.