CHARLESTON, South Carolina (PNN) - January 19, 2012 - Newt Gingrich hit back forcefully on Thursday at an allegation that he asked his second wife to tolerate an "open marriage," angrily denying the claim at a presidential debate in South Carolina.

"I think the disruptive, vicious, negative nature of news media makes it harder to govern this country," Gingrich fumed at the debate moderator, John King of CNN. "I am appalled that you would begin a presidential debate on a topic like that."

Gingrich's wife said in an interview the Republican presidential candidate asked her to have an "open marriage" while he was having an affair with another woman in the 1990s, a statement that might damage his chances in South Carolina's primary vote.

Gingrich, former speaker of the U.S. House of Representatives, is rising in the polls ahead of Saturday's primary vote in South Carolina in which he is campaigning as the conservative alternative to Mitt Romney.

His Republican opponents were asked whether Gingrich's past infidelity should influence the campaign.

"Let's get on to the real issues," said Romney.

Rick Santorum, who is challenging Gingrich for the votes of social conservatives, talked about faith.

"This country is a very forgiving country," Santorum said. He adds that it's up to voters in South Carolina to decide if the matter is relevant.

Ron Paul said the attacks on Gingrich are being generated by media. But he adds that he's proud his wife of 54 years is with him.