This and approval polls, in general, seem to confirm that polls still massively underestimate Republicans in the Midwest and underestimate Democrats in the west and some southern states (but to a lesser extent).
We just had elections at almost Presidential turnout levels that showed that there wasn't a massive understatement of Republicans in the Midwest.
Indiana, Missouri, Ohio Senate races. Michigan as well (tightened towards the end, but still overall underestimated James). Even Iowa and Ohio governors races. There were only two major competitive states that underestimated Democrats (Nevada and Texas) both in the Southwest. Even though the examples I mentioned above are not as extreme as what happened in 2016, it's still significant that the polls are almost all off in one direction in a significant part of the country.
Do we really think going off approvals, for example, Virginia is going to vote to the right of Iowa? Wisconsin and Michigan to vote to the left of Nevada?
