Mitt Romney and John McCain sought to enhance their stature in a field of Republican presidential contenders that Newt Gingrich derisively called "pygmies," criticizing their Democratic rivals as too liberal and ill-prepared for the nation's top job.

Romney, the former Massachusetts governor, singled out Democratic front-runner Hillary Rodham Clinton, telling senior citizens in central New Hampshire, "I don't think Hillary Clinton could get elected president of France with her platform. France is moving toward us."

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Romney did not spare others, though, saying, "I'm convinced that America is going to change course and the question is which way it is going to go: Are we going to take a sharp left turn represented by Hillary Clinton and Barack Obama and John Edwards, or are we going to march forth with the American values that have always helped us be the strongest nation on earth. And I believe we'll do the latter."

The Republicans' criticism of their Democratic counterparts comes amid national polls that show the White House race is far more volatile on the GOP side than on the Democratic side. The latest Associated Press-Ipsos poll found that nearly a quarter of Republicans are unwilling to back top-tier hopefuls Rudy Giuliani, Fred Thompson, McCain or Romney.

In sharp contrast, the Democratic race remains static, with Clinton holding a sizable lead over Obama.

Criticizing Democrats is one way for Republican candidates to appeal to the party's core voters.

Romney, meanwhile, was in Bedford, N.H., talking up his support for a ban on assault-style weapons. He said he sees no problem with a Manchester City Republican Party's fundraiser next month where guests will fire Uzis and M-16 rifles.

"No one is suggesting that automatic weapons be made available to the public," Romney said at a town hall meeting in a school gym. I support the Second Amendment."

Romney said using a weapon is different from owning one.

"I've held the stick on an F-16 fighter jet," he said. "That doesn't mean I think the public ought to be flying F-16 fighter jets. Let the Manchester Republican Party do as it likes."

McCain took exception to remarks in which Obama asserted his foreign policy judgment was superior to any of the candidates in the race, Republican or Democrat, partly because he has lived overseas and had a multicultural upbringing.

"Well, I also think I'm the most qualified to run the decathlon because I watch sports on television all the time," the Arizona senator said with a degree of sarcasm between stops in this leadoff primary state.

"I think that Senator Obama showed a degree of naivete when he advocated direct talks with the leader of North Korea and the president to Iran and of all these other people who are sponsoring terror all over the world," McCain told The Associated Press.

The Democrats turned on themselves this week, after Obama said at a debate on Monday that, as president, he would be willing to meet with certain world leaders perceived as hostile to the United States without preconditions.

Clinton was more cautious, saying she didn't want the prestige of the presidency used for foreign propaganda purposes. She, as did McCain later, called Obama's response naive.

"One thing I'm very confident about is my judgment in foreign policy is, I believe, better than any other candidate in this race, Republican or Democrat," Obama said at a private event in New York City Tuesday, according to his campaign.

"And I don't base that simply on the fact that I was right on the war in Iraq. ... What I was drawing on was a set of experiences that come from a life of living overseas, having family overseas, being able to see the world through the eyes of people outside our borders," Obama said. "The notion that somehow from Washington you get this vast foreign policy experience is illusory."

Responding to the GOP criticism, Kate Bedingfield, a spokeswoman for Edwards, said of Romney, "No candidate is more out of step with the nation than Governor Romney, who supports President Bush's stay-the-course strategy in Iraq while the vast majority of Americans are demanding a new plan that brings our troops home safely and swiftly."

Both Romney and McCain had active campaign days, with Romney making seven stops across central New Hampshire and McCain holding three events across the central and southern part of the state.

The normally secretive Romney let slip a few details about his upcoming campaign agenda, saying he will outline his national health care plans, and that he and his staff have been studying abuse in the federal Earned Income Tax Credit program.

Romney also shrugged off Gingrich's remark this week that the GOP field is a "pathetic" bunch of "pygmies." Gingrich is a potential GOP candidate.

"I consider it an exceptionally strong field and think they're good people that folks will be able to choose from. And if Speaker Gingrich wants to get in, he would enhance the field," Romney said.

McCain was less charitable when asked about Gingrich's comment on Tuesday.

"If Mr. Gingrich decides he wants to get into the presidential campaign for the nomination of our party, then I would take some of his comments more seriously," the senator said.

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