New Jersey Gov. Chris Christie isn't shy about playing Mitt Romney's attack dog.  This morning on "Meet the Press," he said Newt Gingrich has been "an embarrassment to the party," citing his ethics violation and the fact that he was thrown out as speaker of the House by his own party.

Gingrich, on the other hand, showed this morning that he is his own best attack dog, suggesting that Romney's arguments on Bain wouldn't stand up to "a high school debater."

Gingrich suggested his own debate performance was a big contributor to his success in South Carolina.

"One of the reasons I think people in South Carolina voted for me is the  belief that I could debate [President] Obama head to head and convey American values," he said. "We need somebody who can win the debates and try to undo the damage that [the Obama campaign] will try to do with their billion-dollar campaign."

The former House speaker said Romney's decision to attack him over his ethics investigation is "bizarre," because while Gingrich's  entire 1,300-page ethics committee report is available online, Romney's records as Massachusetts governor were "erased" from the state's computers.

"Gov. Romney is trying really hard to avoid answering anything," Gingrich said on "Meet the Press." "They cleansed every single computer and have no real record of how they developed [the state health care law critics call 'Romneycare']."

After calling for Romney to release his tax returns for weeks, Gingrich commended Romney's announcement this morning that he will put out his returns on Tuesday.

"I think that's a very good thing he's doing," Gingrich said. "That particular issue is now set aside and we can go on and talk about bigger and more important things."