Unironically this. I think they would swing hard to a libertarian GOP and stay there after a generation. But it wouldn't have the longest streak.
Barring the second district, I say Nebraska. Historically loyal unlike the South, no majority minority groups capable of overnight elasticity like Mormons, not small enough to be drastically affected by carpetbaggers like Wyoming and West Virginia, not experiencing short-term demographic changes like Texas or even long-term like Kansas. Only thing that could throw it off is a farm crisis brought on by the Ogallala Aquifer drying up, but who's to say national Republicans won't address that in a way that appeals to Nebraskans? The GOP would change fast if it meant losing their base region.