Romney lost because he made the election a referendum on Obama.
Romney lost because the Romney/Ryan ticket was not conservative enough.
Romney lost because the media was on Obama's side.
Romney lost because of Newt Gingrich.
Romney lost because of Chris Christie.
I'm not what you call a "pundit" or an "analyst" or a "political insider". I just have a feeling that the real reason Romney lost is because on any given issue, he was opposed by the majority of the electorate. Sure, combine that with not being particularly likable on a personal level and running a poor campaign, but the real reason is that the policy was wrong on just about every single issue.
This, of course, is the hardest thing for the GOP to accept, and the fate of their party on a national level will hinge on whether they grasp this fact or not.