Bedford, N.H. ? Call them Mr. Rough and Mr. Smooth. Or maybe Mr. Nasty and Mr. Nice. The intense battle between Rudy Giuliani and Mitt Romney for supremacy in the Jan. 8 New Hampshire Republican presidential primary is more a contrast in personalities than a difference on issues.

Watching them in back-to-back appearances over the Thanksgiving holiday weekend – a mix of parades, home visits and town meetings – it became evident that, much as these men dislike each other, they are locked in a political contest that virtually excludes outsiders.

John McCain has retained some of his backing from 2000 in New Hampshire and libertarian Ron Paul has his own fervent faction. Mike Huckabee appears to be a lesser player here, but could gain momentum if he upsets Romney in Iowa. Fred Thompson’s campaign is a puzzle to local Republican leaders.

But Giuliani is laying down a serious challenge to early leader Romney, and the buzz in GOP circles is all about the sharp contrast in their styles.

Giuliani uses blunt instruments – almost daring his audiences to defy him. He begins even informal, house-party talks with the flat-voiced declaration, “I am running for president of the United States.” Implicit in his tone is the unasked question, “Want to make something of it?”

He has so far defied the conventional wisdom which declares that a pro-choice, anti-gun, pro-gay rights double divorcee on his third marriage cannot win the Republican nomination. Brushing all that aside, he refuses to feign any false modesty, saying he is running because “I can accomplish things that others try to do and fail.” The examples he cites are, in his telling, a record of cutting taxes, cutting welfare and cutting crime in New York City. Message: I can take on a tough Democratic city and whip it into shape, and I will be equally tough on Hillary Clinton.

More than any of his rivals, Giuliani is pitching his campaign to that prospective race. He regularly rips Bill Clinton for cutting back the armed forces and “gutting” the intelligence services and, in an interview, said he envisages challenging Hillary in Michigan, California, Oregon, Washington, Wisconsin and much of the Northeast.

But he is a rough-edged campaigner, rarely bothering to engage his crowds at the personal level with friendly banter or jokes, and given to long, boring answers even to sympathetic questions. His paeans to French President Nicolas Sarkozy leave some in his audiences baffled, and occasionally he has to be reminded to talk about terrorism – supposedly his strong suit.

His real subject is himself, and he brooks little criticism. When I asked him if it was true, as I had read, that he fired William Bratton as police commissioner because Bratton was getting too much credit for New York’s drop in crime, he replied, “I didn’t fire him. He resigned.” Then he acknowledged that “we had some differences about the publicity operation in the police department. I thought after three years that it was time for new leadership.”

Romney is at the other extreme, so smooth he appears slick. At a town meeting in Bow, he began by introducing his son Craig, then said, “I wish Ann (his wife) were here,” then, further underlining the family values theme, declared “I’m in this race, because I’m really concerned about my kids and your kids.” He ticked off the challenges they may face, from “global jihad” to the emergence of China and India as economic powers to the Democrats expanding government and raising taxes.

As he outlined his views, they were not much different from Giuliani’s, but the tone was far more conversational. When he got to the question period, he answered crisply, satisfying more than twice as many members of the audience as Giuliani did. He played especially to a 9-year-old girl who asked about his education policy, telling her, “I’m going to make your school harder, ’cause I want you to have the best education in the world.” He drew much more applause with such brief and pointed answers than Giuliani did with his rambling responses.

At the end, however, there is a sense of a really studied performance at the “Ask Mitt Anything” sessions. They raise the question: What lies behind this polished facade? Romney is a superb personal campaigner, as I have seen previously in his two Massachusetts races. But the Romney running for president has different beliefs than the Romney who ran for senator and governor, and the puzzle persists: Which Romney would serve in the White House – Romney the moderate or Romney the Reagan conservative?