The states I worry about are the large population of voters 25-35, and the states with large union populations.
So that IMO takes it down to the normal Democratic states - The Republicans better turn out very large numbers in the middle of the country to offset, New York, Illinios, Michigan, Ohio, California, Oregon and Massachusetts. These states as we all know generally go Dem. The good thing in Mich., Illinois and Ohio is the union membership is the lowest it has been since the 30's, about 9% lower so they don't control as many votes, but watch out for the 'Chicago Vote Machine'. Any of the heartland states with large populations mentioned above could be problems. The three states that worry me is not because of the number of EV's, but the coming very high popular vote, and those are Alabama, Georgia and Louisiana, that were considered mostly Rep. states in the past, or in the Louisiana case the hurricane backlash. The 25-35 age group turn out is going to be very high there.