Here's a map of raw swing (not trend) between 1996 and 2016. Note that even though the country moved 6 points right, 13 states and DC actually moved leftwards:
(Note that states colored the lightest Republican tone here trended left outright, as did a few of the states in the next color that trended the least). My main notes of surprise here are being reminded of just how strongly New England voted left in 1996 (Massachusetts did trend left between 1996 and 2016, but only by the narrowest of margins: it shifted 6.1 points right, compared to the US shifting 6.4), and of how much less Hispanic the US was in 1996; I don't think of Nevada or New Mexico as states where Trump did particularly poorly, but they're represented here as places that swung left even as America moved 6 points right.
Here's a slightly more interesting map, I think: 1996-->2020 swing. Some of the weirdest artifacts of 2016 are gone, and this is only a 4-point shift right, so it shouldn't be quite as ridiculously skewed in favor of the GOP:
Much better. The map with Massachusetts not indicated as one of the states shifting Democratic was giving me a headache.
