I worry less (some, but less) about PA/MI/WI - obviously these are and will continue to be swing states (and in fact, have been for a while if you look at the '00 and '04 results - Obama made them look bluer than they ever were). But I struggle to believe that any will be "gone" for the Dems (e.g., will remain very light blue or at worst, purple). Population shifts out of the rural areas in these states, and continuing room for Dem gains in the more rapidly growing suburbs, has me a little more optimistic about these states than the average Dem. I would be more worried if they were vital for a path to 270 (if anything, they're much more vital for a Senate majority).
PA voted 3.6 points right of the NPV, Wisconsin voted 4.1 points right of the NPV, those are both a non-insubstantial trend right from 2016. Michigan trended left by about half a point, to 1.9 points right of the PV. And this was with Joe Biden as the nominee. Do you think Bernie, Warren or Buttigieg would have seriously won WI or PA? Believing they will remain tilt D is wishful thinking.
The bottom hasn't fallen out for rural Democratic support yet in WI or MI. PA is closer to maxed out for the GOP since the middle of the state is culturally appalachian, and votes like it, but Biden was the best candidate to flip it back with areas like Erie and the Philly suburbs.
I don't think they will "remain tilt D" but I do think there may be more cause for concern with Nevada, and that thinking they'll be permanently Lean R (or worse) in a few years is also wishful thinking. I obviously know what the trends have been; I also know that the rural areas (where there may or may not be further room for Ds to fall) are stagnant or shrinking while the suburbs both continue to trend D and continue to get larger. I just think they will be very, very purple for quite a while. Also, I am not one of those Dems who thinks the Midwest will revert back to 2012 levels without Trump on the ballot, but we do need to see what impact this will have on both turnout and swing voter outcomes. 2018 probably isn't the best proxy since it was such a great year for Dems; 2022 may be more informative.
The strategy is to hold enough of the rust belt until there's enough votes in the sunbelt to make up for losses there. Basically, get Georgia, and preferably Arizona to be lean D, NC and NV both to be even odds, and to be able to realistically compete in TX or FL and do it all before at least one of WI,MI, or PA become out of reach.
