https://uselectionatlas.org/FORUM/index.php?topic=165066.0The amazing 2000-2012 swing map above indicates that some of the largest Dem-swings have occured in the Rocky Mountains - not only in Colorado, where it might have been expected to some extent, but also in Southern & Western Wyoming, Western Montana and Northern Idaho. Obviously, the Romney/Mormon effect distorts the picture in and aroud Utah, but even there, we find places like, e.g., Summit County UT swinging Democrat.
The Rockies have none of the classical D-leaning characteristics - neither are they urban, nor blue-collar, nor characterised by strong minority populations. So, what is going on there?