Interesting ... I would have guessed that both the coasts would be mostly green-ish and the central parts mostly red-ish (shows you what I know about US demographics!).
Looks like a lot of this is due to fracking for oil in regions they are not exactly boom towns to begin with. Frackers are going to make a lot more than what the median wages in these areas, most of them are way are out in the boonies.
Take North Dakota, east Texas, or Alaska . The 10 highest paid jobs are all related to oil fracking, not to mention how desolate these places are.