Mitt Romney is greeted by supporter Joni Scotter at a town hall meeting at the Diamond V South Plant in Cedar Rapids, Iowa December 9, 2011. (JIM YOUNG/REUTERS)

Romney demurred when asked here Friday whether he agreed with some of his supporters, who in a Thursday offensive organized by his campaign characterized Gingrich as vain, erratic and untrustworthy. The former Massachusetts governor limited his criticisms of Gingrich to the former House speaker’s views on Medicare, highlighting Gingrich’s comments this spring when the former speaker called House Budget Committee Chairman Paul Ryan’s (R-Wis.) Medicare overhaul “right-wing social engineering.”

“Speaker Gingrich and I have a very different view, for instance, with regards to Paul Ryan’s plan and the need to fundamentally transform Medicare 2.0, if you will,” Romney told reporters here. “We’ll talk about those differences and, I think in the final analysis, the American people will decide who can best lead our country in a very critical time.”

Romney declined to comment on a negative advertisement created by a political action committee run by his former aides that says Gingrich has “a lot of baggage.”

Romney also did not say whether he agreed with what his supporters – including former White House chief of staff and New Hampshire governor John Sununu – said about Gingrich’s leadership. But he didn’t disavow their comments, either.

“I can’t write a script for Governor Sununu or anybody else,” Romney said. “I can tell you that the people who’ve worked with Speaker Gingrich have their own views and they’ll express those views. … As for the comments of other folks who are supporting me, I don’t write the scripts for them.”

Earlier, at a town hall meeting here in Cedar Rapids, Romney framed the election as a referendum on leadership. When a voter stood to ask Romney why he thinks he is the best debater in the Republican field, Romney said: “I will be able to demonstrate a record of leadership.”

“When you think about our great presidents – Washington, Lincoln, for me, John Adams, Ronald Reagan, George H.W. Bush, Eisenhower, J.F.K. – what distinguishes them was the capacity to lead,” he said. “Their character, their vision, their ability to bring other people along, to convince others. The capacity to lead is what we need in America’s president. The leader of the free world needs to be able to lead.”

Making about ten minutes of opening remarks on the floor of an animal-feed manufacturing plant, Romney sharpened his critique of President Obama. He drew loud cheers from the audience of about 200 when he said he believes the president “doesn’t really understand America.”

“He means what he says when he says he wants to fundamentally transform America,” Romney said. “There’s nothing wrong with America that needs transforming. I want to restore America. I want to turn around America.”

One man asked Romney whether he would condemn Muslims. “Are you going to continue to give Islam and Islamic jihad in this country a pass like everybody before you has continued to do?”

Romney responded by saying he would “take the battle to jihadism in an aggressive and dynamic way,” but that he would not condemn all Muslim people.

“I was raised in Detroit,” Romney said. “The city next door to Detroit is called Dearborn, Michigan. It has a very large Arab and Muslim community. They are peace-loving and America-loving individuals. I believe that very sincerely. I think people of the Islamic faith do not have to subscribe to the idea of radical violent jihadism.”

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