Biden's lead in our polling averages before/after these polls:

MN +6.4 -> +7.4
NH: +8.4 -> +6.9
NV: +6.5 -> +5.9
WI: +6.9 -> +6.5 https://twitter.com/Nate_Cohn/status/1304754901902340102

So Biden's losing ground in 3 of 4, but the one where he's gaining (MN) is arguably the most important of the four. Why? WI has been polled a ton, so no one poll will influence our model that much. The other 3 haven't been polled much, but MN has more electoral votes than NH+NV.

Of the four key Midwest/Rust Belt battlegrounds, we're getting a pretty clear hierarchy where WI and PA are more competitive than MI and MN. You wouldn't go so far as to say Biden doesn't need to worry about MI/MN, but they've become less likely tipping points.