As I recall Mitt is the guy whose son said he didn't really want to be president after he lost, and from what I saw during the debates there is no arguing with that.
I don't buy this for one second. It sounds like college fans who don't get a recruit and suddenly proclaim 'we didn't really want him, anyway.' In other words, a total rationalization. Mitt Romney wasn't going to waste millions of dollars of his own wealth trying to lose.