Republican presidential candidate and former House Speaker Newt Gingrich speaks during a South Carolina Republican presidential primary night rally Saturday in Columbia, S.C. (Matt Rourke/AP)

Watts said Gingrich, a former House speaker, was never a part of the discussions on Capitol Hill about Freddie Mac. He criticized Romney for accusing Gingrich of lobbying for Freddie Mac because it isn’t true -- and because it’s hypocritical to blast Gingrich for hiding the nature of his work when Romney took steps to conceal public records pertaining to his service as Massachusetts governor.

Watts, a former four-term congressman from Oklahoma first elected with the Republican revolution that Gingrich led in 1994, is a former chairman of FM Policy Focus, an arm of his Washington consulting firm that represented various financial institutions who were pushing for greater oversight of Freddie Mac and Fannie Mae.

Republican presidential candidate, former Massachusetts governor Mitt Romney, campaigns at Allstar Building Materials in Ormond Beach, Fla. on Sunday. (Charles Dharapak/AP)

“In the six years that I was chairman of FM Policy focus, we had Republican and Democrat consultants that were part of our meetings,” Watts said. “We talked to Republican and Democrat members of Congress. We talked to Wall Street types. And the first time I heard Newt Gingrich’s name was probably 45 days ago, and that was probably that first week of December, when he was getting hit in Iowa basically saying that he was peddling influence for Freddie Mac.”

At issue is Gingrich’s work for Freddie Mac, for which he was paid more than $1.6 million. Gingrich repeatedly has said that he never lobbied lawmakers on behalf of Freddie Mac and health-care companies, saying he was paid for his services as a consultant and historian.

“I was not a lobbyist, I was never a lobbyist, I never did any lobbying. Don’t try to mix these things up. That fact is I was an adviser strategically,” Gingrich said Sunday on “Meet the Press.”

The Gingrich campaign arranged for the media conference call with Watts in answer to the barrage of attacks coming from Romney’s campaign. Seeking to blunt the momentum of Gingrich’s huge primary win in South Carolina on Saturday, Romney has called for Gingrich to release his contracts with Freddie Mac and also to release documents relating to a House ethics investigation against him when he was speaker. As the two frontrunners seek to gain advantage in advance of Florida’s Jan. 31 primary, it became clear Monday that one way both would do that is to relentlessly attack the other.

Gingrich’s work for Freddie Mac represents a key weakness for him among Republican voters, who have long viewed the federally backed mortgage provider with suspicion. Gingrich, meanwhile, plans to go after Romney on his advocacy for a health-care overhaul in Massachusetts that served as a model for President Obama’s health-reform bill, which is deeply unpopular among Republicans. A pro-Gingrich super PAC will also continue to hammer Romney on his leadership of venture capital firm Bain Capital, particularly its takeover of Damon Clinical Laboratories, a company that was fined $120 million amid accusations of Medicare fraud.