1. New Hampshire: pretty easy both ways. State Senate is a gerrymander but the median seat is 50-50
2. Michigan: fair map, both houses tipping point seats are Dem favoured but in a republican wave they could flip
3. Pennsylvania: Same as above both houses of the legislature are balanced
4.Virginia: Democrats favoured in both maps but not too an unshakeable degree.
I'm pretty sure that's it, the rest of the swing states have a part of the state legislature that's too gerrymanderd to flip bearing a huge wave.
MN: fair map drawn by SC. Both houses are lean D but can be flipped in a good year like 2014 and 2016.
ME: a little harder to flip, but still doable in 2010ish environment.