Considering Utah is never going D, Romney would be a welcome addition as a Senator from Utah.
It would take a perfect storm, but there's the potential for that this year.
1. Matheson - former Democratic Congressman who was able to win in a very red district several times, even surviving 2010 - would probably be favored against Hatch, tbh.
2. Orrin Hatch has awful approval ratings for a Republican in Utah, and most people would prefer that he retire, according to various polls.
3. McMuffin running as an Independent is a possibility. That may or may not hurt the Dems if he runs, but because it might help them, I'm including it.