GINGRICH: He’s adding some members to his South Carolina team, including Sally Atwater, daughter of Republican strategist Lee Atwater; Adrian Grimes, who worked in Rep. Tim Scott’s communications department; and Anne Badgley, the founder of a crisis pregnancy center and abstinence education advocate, NBC’s Ali Weinberg reports. Atwater, a senior at Furman University in Greenville and vice chairman of the South Carolina College Republicans Federation, will head the campaign’s South Carolina Young Republicans coalition.

Getting coverage in South Carolina is Gingrich leading in a new Clemson poll, showing him up 38%-21% over Romney. (But a MAJOR caveat here: It was conducted from Dec. 6-19, a very long time to be in the field and a lot of things have happened over those two weeks.)

“Presidential candidate Newt Gingrich called on his supporters last night to demand that all negative ads targeting him be removed from the airwaves,” the Boston Globe writes. Gingrich said in Davenport, IA, “It’s very disappointing to see some of my friends who are running putting out so much negative junk.”

HUNTSMAN: Our Destiny PAC (a pro-Huntsman Super PAC) has a new ad out, which pushes that he’s a “consistent conservative,” NBC’s Jo Ling Kent reports. It also took out a full-page ad in the New Hampshire Union Leader touting Huntsman as "more conservative than Mitt Romney and Newt Gingrich combined."

ROMNEY: On “Morning Joe” this morning, Romney was asked if he believes Gingrich is the front-runner. He cited that Gingrich still has a lead in national polls, but pointed out it’s not as big as it had been, and then said, “I suspect he’ll lead until he doesn’t lead.”

Asked if he would call on a Super PAC (Restore Our Future) supporting him to stop negative attacks, Romney laughed and said, “It’s illegal” and that if he did he would go to the “big house.” He then pivoted and said campaign-finance laws have made a “mockery” of the political system. And said the country should “get rid of these super PACs.”

He has criticized Gingrich as a “life-long politician” and said there’s “nothing wrong with a life-long politician. We have one in the White House right now.” He also praised Gingrich, in part, for the Contract with America, something he once criticized.

He dismissed the notion that he can’t win over conservatives, saying that 25% in the polls at this point is high historically. And he said he has dealt with rejection, noting when he was a missionary for the LDS Church in France he knocked on doors for five months and “didn’t convert one person.”

He downplayed his chances in Iowa. Asked if he had to win New Hampshire, he said, “Today, you don’t HAVE to win anything.” And cited the number of delegates needed to win the nomination instead.

On O’Reilly last night Romney “criticized both his Republican rival and the Democratic president he hopes to face next year, calling the ideas of Newt Gingrich ‘not practical’ while saying that if President Obama is reelected the country will ‘hit a Greece-like wall,’” the Boston Globe says.

On with Charlie Rose last night, Romney acknowledged that his biggest weakness is authenticity, per the Boston Globe:

ROMNEY: “I have a friend who said to me, ‘Every candidate has a but,’ I said, ‘What do you mean?’ They said, ‘Well, so and so’s great but -- and so and so’s great but --.’”

ROSE: “Romney’s great but …”
ROMNEY: “Oh, but he’s not authentic.”

He also “suggested that at town hall meetings and other settings people often leave saying, ‘Hey, that guy connects pretty darn well with people.’”

He did the Top 10 on Letterman last night. It included, per NBC’s Garrett Haake: “No. 2: Newt Gingrich, Really?”