Aside from the Mormons, this seems to have nothing to do with any personal appeal or lack thereof of Mitt Romney. It's just a combination of: the appeal or lack thereof of Barack Obama + which states were contested + demographic changes. To the extent that many of us (including, occasionally, me) on the forum were wrong about our sense of the swing in certain regions (and social classes), it had to do with not predicting this. It's as if maybe Romney, after all his contortions, just didn't stand for anything distinctive in the minds of voters except generic R/not-Obama.
Nailed it, I think.