Newt Gingrich and Mitt Romney have engaged in a war of words over negative campaign ads.

Romney has been able to sit back and watch Gingrich slide in the polls, thanks in part to the negative campaign ads by GOP rival Ron Paul and by pro-Romney super-PAC Restore Our Future.


"You can't turn on a TV, you can't swing a dead cat, without seeing a negative ad [in Iowa]," said GOP strategist Frank Luntz on Fox News Monday. "Speaker Gingrich does not have the money to respond."

Gingrich, whose campaign was in debt as he began to rise, has also maintained that he will run a positive campaign.

“The only person who profits from Republican ads attacking other Republicans is Barack ObamaBarack Hussein ObamaWe must eliminate nuclear weapons, but a 'No First Use' Policy is not the answer Building back a better vice presidency Jill Biden unveils traditional White House holiday décor MORE. I think it is pretty reprehensible behavior on the part of some of the candidates,” Gingrich said Monday, according to multiple reports.

Paul's campaign has been running a series of ads accusing Gingrich of "flip-flopping" and "selling access" to Washington — and the candidate himself has spoken out more than once, calling Gingrich "immoral" for collecting a consulting fee from mortgage lending giant Freddie Mac.

But it was Romney whom Gingrich criticized for running negative ads.

His campaign “ought to be ashamed of themselves," Gingrich said. “If you see Romney, tell him to take them off the air."

The pro-Romney super-PAC Restore Our Future spent $2.4 million in December on media production, distribution and direct mail opposing Gingrich. The group, founded by former Romney aides in 2010, is running TV ads in Iowa, which holds its caucuses Jan. 3, and spent $300,000 on an ad buy in Florida, where the primary vote is set for Jan. 31. The ads hit Gingrich as the "least conservative candidate" on illegal immigration, climate change and the infamous Freddie Mac payments.

Responding to Gingrich on MSNBC on Tuesday morning, Romney pointed out it would be illegal for him to tell the super-PAC to stop running negative ads.

"I'm not allowed to communicate with a super-PAC in any way, shape or form," Romney said. "If we coordinate in any way whatsoever, we go to the Big House."

Campaign finance laws forbid coordination between campaigns and outside spending groups.

Bill Allison of the nonprofit Sunlight Foundation called super-PACs the "shadow campaigns" of 2012.

“The advantage is they can run the negative advertising without it coming back to bite the candidate — having this other vehicle to do that kind of dirty work allows candidates to be positive in their ads," he told the nonprofit Center for Public Integrity.

Although Romney has likely benefited the most from the super-PAC's campaign against Gingrich, he went on to advocate reforming campaign finance law — particularly the provisions that allow super-PACs to raise unlimited funds while campaigns have to stick to limits.

"I think it is a disaster ... campaign finance law has made a mockery of our political campaign season," Romney said. "We really ought to let the campaigns raise the money they need and just get rid of these super-PACs."

Romney has also made it clear that the GOP candidates should be able to handle a few negative ads.

“If I can’t handle a few attacks coming my way and the other guys can’t, then boy, we’re not going to be ready for Barack Obama,” he said last Friday on Fox News.