The dizzying array of polls coming out for the Michigan and Arizona primaries are all over the place. One Arizona poll has Romney up 16 points while another has him leading only by 4.

In Michigan, you pick 'em. NBC has Romney up 2 while Rasmussen has Santorum up 4.

What is going on?

This kind of volatility can only mean that GOP voters have not made up their minds. I think it pretty clear that they would prefer someone other than Mitt Romney lead the ticket. But they are hardly sold on Rick Santorum as the alternative. More moderate libertarians and Republicans are worried about Santorum's social conservatism while even some fiscal hawks question his committment to cutting the budget.

Romney has become the de facto fallback candidate. If all else fails, Mitt is there, ready and waiting. You can't quite say the GOP is desperate not to nominate Romney. This is evident in their hesitation in supporting Santorum. But Santorum's biggest plus is still that he is the number one "not Romney" candidate and that seems to satisfy few Republican voters.