Romney surrogate: "I wish this president would learn how to be an American."

The Romney campaign ratcheted up its language on Tuesday in a conference call on which former New Hampshire governor and White House chief of staff John Sununu said he wished President Obama "would learn how to be an American."

"The president clearly demonstrated that he has absolutely no idea how the American economy functions. The men and women all over America who have worked hard to build these businesses, their businesses from the ground up is how our economy became the envy of the world -- it is the American way," Sununu said in his opening remarks of the conference call.

He added: "I wish this president would learn how to be an American."

The first question to Sununu later in the call was about that comment, which exploded quickly on Twitter for its stark claim about Obama.

"What I thought I said, but I guess I didn't say, is that the president has to learn the American formula for creating business," he said. "If I didn't give all that detail I apologize."

The Obama campaign's Lis Smith said that Sununu's rhetoric represented that the Romney campaign had grown desperate.

“The Romney campaign has officially gone off the deep end," she said. "The question is what else they’ll pull to avoid answering serious questions about Romney’s tenure at Bain Capital and investments in foreign tax havens and offshore accounts. This meltdown and over-the-top rhetoric won’t make things better -- it only calls attention to how desperate they are to change the conversation."

Regardless of the walk-back, the tone of the call was consistently negative -- and harshly so -- with Sununu and the four small businesspeople on the call ripping the president's policies, background and campaign tactics.

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