I think it looks like the Electoral College's partisan bias in the 2020 Presidential election is the largest bias since 1936. The data for this calculation is at dbaron.org/presidential-elec… . (Let me know if there's an error!)

How do you handle Nebraska and Maine?

Treat the congressional districts as though they're separate states, for the purpose of their electoral votes. (Though the first time I calculated 2008 I messed that bit up!) Interestingly, the *difference* between the 2016 and 2020 tipping points was NE-2 becoming D-leaning.