Mitt Romney's been called a lot of things on MSNBC. But when a Romney surrogate called President Obama "lazy," it seemed to go too far for anchor Andrea Mitchell -- who suggested her guest take it back.

Mitchell was responding to characteristically feisty remarks by John Sununu, the former New Hampshire governor and top Romney surrogate known for his hard-edged slams against Democrats.

Assessing Obama's performance at the debate in Denver on Wednesday, Sununu said: "What people saw last night I think was a president that revealed his incompetence, how lazy and detached he is and how he has absolutely no idea how serious the economic problems of the country are."

Later in the interview, Mitchell nudged Sununu to reconsider that remark.

"Governor, I want to give you a chance to maybe take it back. Did you really mean to call Barack Obama, the president of the United States, lazy?" she asked.

"Yes," Sununu responded. He repeated the claim and referenced a comment Obama had made earlier in the week in between debate prep sessions in Las Vegas. The president said "it's a drag" and that his aides were "making me do my homework."

Mitchell, though, pressed Sununu again.

"I think that there certainly was a performance issue there and whether or not he was in his best form last night, a lot of people are questioning that. Just the one-on-one against Mitt Romney, Mitt Romney turned in a very strong performance. But I think to call the president lazy and disengaged is another whole question," she said.

"All right, Andrea, whatever," Sununu concluded.