Why didn’t any of the 2012 candidates attack Mitt Romney in Iowa?

DES MOINES, Iowa--Mitt Romney has long been considered the frontrunner for the 2012 Republican presidential nomination, but if he wins Iowa's caucuses on Tuesday, it will be partly because of one extraordinary fact: Not one of his Republican rivals ran a negative TV ad against him in the state.

Sure, Romney was sometimes mentioned in the onslaught of attack ads that swept Iowa airwaves in the final days of the campaign. Ron Paul ran a television ad trashing Romney and Newt Gingrich as members of the status quo who won't bring the leadership necessary to really change Washington. And Make Us Great Again, a super PAC backing Rick Perry's candidacy, ran ads that took aim at Romney and Gingrich, questioning their conservative credentials.

But none of Romney's 2012 rivals ran an ad solely taking on the former Massachusetts governor—a sign that they perhaps underestimated his rise in Iowa.

Just 20 percent of the negative ads airing in Iowa targeted Romney, even as part of an attack on multiple candidates, according to the Campaign Media Analysis Group. By comparison, 45 percent of the negative spots went after Gingrich—a statistic that explains, in part, why the former House speaker's poll numbers in the state plunged in the final days of the campaign.

In hindsight, the decision to leave Romney untouched appears to be a serious miscalculation, one that Romney's opponents are unlikely to repeat as the focus shifts to New Hampshire's first-in-the-nation primary and onto other key early voting states, including South Carolina, Florida and Nevada.

Our Destiny PAC, a super PAC supporting Jon Huntsman, is running an ad in New Hampshire calling Romney a "chameleon." And both Gingrich and Paul have pledged to take on Romney heading into New Hampshire.

Romney's opponents will have plenty of ammunition, ranging from his health care plan in Massachusetts to his changing positions on social issues like abortion and gay marriage.

"New Hampshire is the perfect state to have a debate over Romneycare and to have a debate about tax-paid abortions, which he signed, and to have a debate about appointing liberal judges, which he did," Gingrich said Sunday.

As his rivals attacked each other in Iowa, Romney used the moment to try to rise above the fray and focus his attacks entirely on President Obama (while his super PAC, Restore Our Future, savaged Gingrich)—a strategy his advisers insist he'll maintain throughout the primary. The big unknown is how Romney will react should the other candidates train all of their firepower on him, as they have threatened to do.

Asked by Yahoo News how the campaign might react to more scrutiny and attacks from the rest of the Republican field, Stuart Stevens, a Romney strategist, paused for several moments while he considered his answer.

"You can never predict in campaigns what happens moment to moment," Stevens finally replied.

Unlike in 2008, when Romney spent millions of dollars on TV ads attacking Mike Huckabee and John McCain, this time he has has allowed his allies to do his attacking for him.

Restore Our Future, a super PAC overseen by several former Romney staffers and supporters, spent millions on negative ads targeting Gingrich and Perry in Iowa. As a result, the Romney campaign was freed up to run positive ads talking up the candidate's character and record.

Whether that can last will be depend on whether Romney's rivals deliver on their promises to get more aggressive.

"I expect people to come after me," Romney said on MSNBC's "Morning Joe" on Tuesday. "If I do well here, I'll have a target painted on me. So I expect other folks to come after me. You know, if I can't stand up to that, I shouldn't be the nominee."

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