1) The Midwest is incredibly elastic.
2) Kobach was a terrible nominee. How bad do you have to be in order for former Republican Governors to endorse your Democratic opponent?
3) Pennsylvania had the court ordered new House map and it helped Democrats big time. PA was extremely gerrymandered before the change. It could have been a D+1 gain, or even no-gain with the old map.
PA New Map doesn't explain how Casey won by 13% & Wolf won by 17%. This is a state Trump won & where a GOP candidate won for the Senate seat only 2 years ago.
PA swung hard away from Trump & to the Dems in a major major way. IA was fantastic, WI & MI had good results, but PA was weird bad for Trump !