Over all, Mr. Biden leads by eight points among white voters in Wisconsin and trails by just one percentage point among white voters in Michigan.
While Mr. Trump’s surprising victory in 2016 lent him an aura of political invincibility, an Upshot analysis of more than 5,000 respondents to Times/Siena results surveys in the Northern battleground states suggests that his winning coalition was always a fragile one. The president’s margin of victory was extremely narrow, and he failed to reach 50 percent of the vote in each of the decisive states. He also did so against an unusually unpopular opponent, Mrs. Clinton.
In the years after her defeat, Democrats agonized over whether their best path to the presidency was to lure back the white, working-class voters who’d defected to the president, or to increase turnout among Democratic voters who may have stayed home or supported minor-party candidates like Jill Stein. The Times/Siena surveys suggest that Mr. Biden is succeeding on both fronts, by at once peeling off a modest but crucial sliver of the president’s former supporters and benefiting from a significant advantage among voters who either backed a minor-party candidate four years ago or didn’t vote at all.
Over all, recent Times/Siena respondents in Michigan, Pennsylvania, Wisconsin, Minnesota, Iowa and Ohio indicate that they backed Mr. Trump by a 2.6-point margin in 2016, the same as his actual 2.6-point margin of victory across the Northern battlegrounds. Now, they back Mr. Biden across all six states.
https://www.nytimes.com/2020/10/12/upshot/polls-wisconsin-michigan-election.html
