As far as red states go, Nebraska is another. Republicans get absolutely massive margins out of most rural counties, while the two most populous counties of Douglas (Omaha) and Lancaster (Lincoln) cast 45% of the statewide vote and are only light blue.
Another red state where this becoming the case is Texas. Unlike most red leaning states where the Democratic strength is overwhelmingly packed into metropolitan areas, it's actually turning into a geographic advantage for them. It's already fairly simple to draw Democratic majority congressional delegations in DRA despite the state being R+5.5, and if IIRC, Beto won 76/150 state house seats despite losing by 2.6 statewide.
The longtime Republican hold on the state as it drifts ever more purple is seriously threatened by this dynamic, which might be a contributing factor to why the Texas GOP is particularly batty in regards to gerrymandering.
