An unlikely state that's giving me pause about the state of political polling right now is... Nebraska https://www.prri.org/research/in-middle-america-nebraskans-struggle-with-a-changing-cultural-landscape/

The state voted for Trump by 25, voted GOP by like 20 in the House vote/
Here are our recent measures there...
PRRI: Trump favorability -4
Morning Consult: Trump approval -4 (that's worse than TX/FL/NC/GA/AZ)
Civiqs: Trump+7 (only a few pts better than OH/TX)

Is it possible that there's a huge rebellion against Trump there? Maybe. Possibly.
But when we polled NE-2 last year (a Trump+2 CD), we had Trump approval at minus-2.
When we polled IA-4, we had Trump+18 approval and got the result about right

(IA-4 neighbors Nebraska and voted about the same for Trump, though much better for Obama)

So maybe there's a Trump rebellion.
Or maybe it's tough to reach rural white voters and, even when they do, may be getting a fairly non-Trump group.
Can't prove it either way, but it's a big gap with my priors, fits a persistent bias in polling, and our data is inconsistent

our data is inconsistent with those findings, to be clear