According to the Post/ABC survey, 55 percent of registered voters who back Mr. Trump say they are very enthusiastic about supporting him, and 32 percent say they are somewhat enthusiastic. Among Mr. Biden’s supporters, just 28 percent say they are very enthusiastic, while 46 percent are somewhat enthusiastic.

Overall, there’s a 12-point enthusiasm gap between Mr. Trump and Mr. Biden. Among the most excited voters, it’s an even bigger 27-point gap.

Pollsters, strategists and political types pay a lot of attention to the intensity of enthusiasm because it offers hints about who is likely to show up at the polls and who is likely to stay home. (We’re assuming “showing up at the polls” will still be a thing in November.) Campaigning in this polarized era is often less about persuading undecided voters and more about driving out your forces.

Here’s The Post on the history:

In May 2012, Mitt Romney, now a U.S. senator, had a strong enthusiasm deficit of 25 points against President Barack Obama in Post-ABC polling. In June 2008, Sen. John McCain (R-Ariz.) was down 33 points on enthusiasm against Obama. In June 2004, Sen. John F. Kerry (D-Mass.) faced a 16-point gap on enthusiasm in his campaign to unseat President George W. Bush. Romney, McCain and Kerry all managed to narrow that gap by November but ultimately lost their elections.

For much of this election cycle, both parties have been fairly energized. While Republicans have appeared slightly more enthusiastic in polling, Democratic turnout surged on Super Tuesday at the beginning of March, with record numbers of voters coming out to vote in the primaries.

So what’s happened over the past month? Oh, just this tiny, life-changing national crisis called the coronavirus.