Romney pivots to Santorum

Mitt Romney's campaign is turning its attacks on Rick Santorum after a poll showed the former senator leading in Minnesota. 

Former Minnesota Gov. Tim Pawlenty (R), a top Romney surrogate, will attack Santorum by way of a noon conference call for his history of supporting earmarks, Romney's campaign announced Monday morning. Minnesota voters go to the polls for their state's GOP caucuses on Tuesday. 

The campaign also emailed "a summary of Santorum's false attacks on Massachusetts healthcare" that provides a laundry list of nonpartisan fact-checking websites' analysis on some of Santorum's statements criticizing Romney's health insurance overhaul in Massachusetts.

The fact-check list comes ahead of a planned healthcare speech from Santorum.

The pushback is nothing compared to the regular drumbeat of attacks Romney and his surrogates have made on Newt Gingrich, who defeated Romney in South Carolina but has placed second to Romney in subsequent contests in Florida and Nevada. 

But it does show that at this point, Romney sees Santorum as a possibly bigger threat than Gingrich. Romney has mostly ignored Santorum through the campaign rather than engage with him.

The former Massachusetts governor won Nevada's caucuses on Saturday by a wide margin, finishing with more than 50 percent of the vote.

This post was updated at 9:44 a.m.

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