If you compare the 2020 election in the mid-west US to 2004, when Kerry won most of the states by a similar margin to Biden, you get some v interesting insights into the changing electoral geography of the region & US generally:

Wisconsin: Both won by a slim margin of c0.5%, but the map looks pretty different. Biden didn't regain historic rural progressive heartland of west Wisconsin where Clinton was wiped out. But he lost by 15% less than Kerry in Milwaukee suburbs & won by 15% more in Milwaukee

Pennsylvania: Kerry did better, won by 2.5 vs. c0. 5. He won some old industrial areas near Pittsburgh & coal region's Luzerne, both since trending heavily red. Biden won bigger in Philadelphia suburbs & Pittsburgh,lost bigger in central PA, & won Monroe, increasingly a NY suburb

Michigan: Biden won by 3.5, Kerry by 4.5. Biden lost once union & Dem strongholds in Bay region & Peninsula & former black holiday spot Lake County (poorest county in Michigan. Voted McGovern in 72. Now Trump 62%). Biden & Kerry got similar margins around Detroit & Flint. But ..

Biden flipped Kent (Grand Rapids), historic urban stronghold of GOP. In 100 years, only voted Dem before in 08, 64 & 36. Also Leelenau, with growing urban retiree population. Bigger margins in university-heavy Kalamazoo & Washtenaw, capital county Ingham & Detroit suburb Oakland

Minnesota: Biden won by twice as much as Kerry (7% vs 3.5),though you wouldn't guess it from 1st glance at the map. Dems have lost old rural strongholds connected to the farmer-labor tradition. But Biden won by 20% more than Kerry in Minneapolis-St Paul & won formerly GOP suburbs

Ohio: both lost, but Biden by much more (8% vs 2%). Dem decline accelerated with Trump has continued in old industrial areas on Lake Erie & esp in the east. Some eastern counties Kerry won are 70% Trump. But once urban GOP stronghold of Hamilton(Cincinnati) went solidly for Biden

Last of all of course, the biggest difference is obviously that, despite their similar performance in this region, Biden won the election & Kerry lost. Which really sums up the most important change in the political position of the mid-west