Former New Hampshire Senator Judd Gregg joined Martha MacCallum this morning to talk about the mud-slinging among Republicans as they anticipate the results in both the New Hampshire and South Carolina primaries.

"I find it very strange that Republicans would be attacking other Republicans because they create jobs and have participated in the market economy," Gregg said of Newt Gingrich's recent criticism of Mitt Romney. "[He's]

added tens of thousands of jobs to the American economy and people have jobs today because of what he did."

Gregg, who is endorsing Romney, commented on an unflattering 28-minute documentary of the former Massachusetts governor, which a Gingrich super PAC plans to release in South Carolina. The documentary paints Romney as a greedy businessman out of touch with mainstream Americans.

"I think it's unfortunate that one Republican would take that view of another Republican, because basically what Mitt did was create jobs in the private sector," he said. "But if Romney is the nominee, it's going to come at him from the president anyway, so maybe it's good to get it out of the way."

Also, hear Gregg's thoughts on Jon Huntsman in the video below.