Janmcn has a valid point. All through this race as everyone's else's favorability ratings have gone up or down, Romney has stayed stagnant at 20 to 25%. He had one high of 25.5%, but then dropped back to his normal range.

This tells me that about 75% of Republican primary voters are looking for anybody but Romney, at this point. What other conclusion can there be.

I think it might be your wishful thinking that there's another explanation.