I reckon Maryland is actually a pretty decent answer. Hawaii loves incumbents (which frankly is the only way a Republican's getting a 49-state landslide), and the triumvirate of Massachusetts, Rhode Island and Vermont can still and have voted for moderate Republicans (which the Republican would have to be). New York could be another one, I guess, but I reckon it's the right sort of state that could consider a certain slant of Republican. Of course, if it was a conservative who was just crazy popular, then the answer would be Vermont.
Republicans, the correct answer is Utah. Oklahoma if it is a crazy popular liberal, but it definitely would vote for the right kind of Democrat.
To who said Mississippi - I reckon Alabama's a better fit. With Mississippi you only need about 20-25% of the white vote to win (which granted is hard), but Alabama's black population is smaller and the polarisation is only slightly better.
I agree with you about Vermont. If a Republican such as Jon Huntsman received the nomination and faced off against a particular weak Democrat, then Huntsman could potentially carry Vermont, albeit barely. In Oklahoma, it seems that the more conservative Republican candidates do the best in the state, so even if it is a Hillary Clinton vs Rick Santorum race, Santorum would still win the state by a landslide even if he was losing big elsewhere.
