I think the next time Republicans win they will win fairly big. I am expecting Clinton to run and win in 2016 and I'm not sure there's much the GOP can do to stop that, except to pray that Obama falls toward 30% approval. But 2020 could easily be reverse 1992, with the Midwest giving out all at once like the Upper South did in 1992:
This actually seems logical, if the Republicans don't expect that they will always be able to pull through down ballot, or at all, in Florida, be able to take North Carolina, Arizona and Georgia for granted and keep expecting a nominal initial advantage in Colorado, nevermind Nevada. Though the above map is a stretch if they think they could win Illinois. That's probably as possible as Democrats winning Texas or at least no more probable than Indiana, South Carolina and Missouri.