There’s somewhere in the neighborhood of 70 to 80 House districts being contested today with some degree of seriousness. You can browse through the consensus forecast, or the race rankings from Cook Political, Larry Sabato’s Crystal Ball, Fox News, or the New York Times for variations on the same basic story.

Looking at the data from David Nir of Daily Kos Political, I threw together a chart of the 80 districts that are to some extent swing seats or districts tonight — 40 Republican seats and 40 Democrat seats — cross-referenced with statewide poll-closing times. (Some states close the polls at different times in different parts of the state).

Collectively, these districts gave Joe Biden 50.4 percent of the vote in 2020 and Donald Trump 47.9 percent of the vote, so on balance they are very slightly redder than the safe districts, which went 51.3 percent Biden, 46.96 percent Trump. (Biden’s national popular vote also includes the District of Columbia, where he got 92.2 percent of the vote to Trump’s 5.4 percent).

Apologies if it’s rather a lengthy chart, but the districts at the top are the ones where we should start getting a sense of how the national race is going in the Atlantic South and the Midwest. Of course, poll-closing times don’t uniformly reflect when results are available; we will have little settled from California or Alaska tonight no matter what.