More than 10 months ahead of the Democratic and GOP nominating conventions, the two party frontrunners already are engaged in general election politics — though certainly not in the same way. [IMGCAP(1)]

Democratic Sen. Hillary Rodham Clinton (N.Y.), with every reason to be confident of nomination, is moving to the center to attract independent voters. Meantime, Republican Rudy Giuliani misses no opportunity to attack Clinton.

In Giuliani’s case, of course, it’s a device to appeal to the GOP base vote, where the NBC/Wall Street Journal found the “comfort level” with a potential Clinton presidency at 14 percent, well behind other Democratic candidates.

The former New York mayor regularly denounces Clinton’s health care proposal as a step toward socialized medicine and declares her weak in the war on terrorism.

In Tuesday night’s GOP debate in Michigan, the second sentence out of Giuliani’s mouth was “and the leading Democratic candidate once said that the unfettered free market is the most destructive force in modern America.” He added, “I mean, just get an idea of where that philosophy comes from.”

(The Clinton campaign declared in response that “Rudy got it wrong” and cited a Clinton appearance on C-SPAN in which she said she believed that unfettered capitalism was “the most radically disruptive force in American life.” She added, “the market is the driving force behind our prosperity, our freedom … but it cannot be permitted to run roughshod over people’s lives as well.”)

Later in the GOP debate, Giuliani used his successful Supreme Court challenge of President Bill Clinton’s line-item veto as a stick to beat his rival, former Massachusetts Gov. Mitt Romney, who criticized Giuliani’s legal action.

In one of the more memorable moments of the evening, Giuliani declared, “You can’t fool all of the people all of the time. The line-item is unconstitutional. You don’t get to believe about it. The Supreme Court ruled on it. … And I don’t think it’s a bad idea to have a Republican presidential candidate who actually has beat President Clinton at something.”

Feisty, combative and taking an orthodox supply-side position on economics, Giuliani did nothing in Michigan to diminish his front-runner status, especially when Romney opined that he’d have to consult lawyers before deciding whether to go to Congress to get approval to make war on Iran.

Making his debate debut, easy-talking former Sen. Fred Thompson (Tenn.) performed credibly, although he had a deer-in-the- headlights look when asked about why America needs a strong dollar.

So far, the presidential race story is that Clinton is sweeping on the Democratic side — now leading nationally by 22 points, with all constituency groups, in all the polled primary and caucus states, now including Iowa, as well as on most leadership attributes, as the candidate Democrats believe most likely to win, and also in the latest fundraising sweepstakes.

The only foreseeable way she could be stopped is for the Iowa support of the third-ranking national candidate, former Sen. John Edwards (N.C.), to flood to the second- ranking candidate, Sen. Barack Obama (Ill.), allowing him to beat Clinton and start an avalanche against her.

She seems confident enough of her lead that, in a Washington Post interview published Wednesday, she began talking about how her experience in past partisan political wars prepares her to form a centrist governing coalition.

In a Pew Research Center poll last month, “tough” was the characteristic that Democratic voters most associated with Clinton, and in her Post interview she made it clear that her centrism would not be of the gentle kind.

“You can’t just wake up and say, ‘Let’s all hold hands and be together.’ You’ve got to demonstrate that you’re not going to be intimidated and deterred by it, and then you can reach out and bring people who are of good faith together.”

The chances are, the general election campaign will be so tough — especially if Giuliani is her opponent — as to stir her obvious combative instincts and challenge her ability to “reach out” afterward.

But will Giuliani be the nominee? It’s far from certain. Giuliani’s national lead has fallen from 18 points in March to 8 at present, according to polling averages assembled by RealClearPolitics.com. Thompson is running second but has not gained ground since his declaration of candidacy in September.

Romney still leads the field by 10 points in Iowa. Giuliani is gaining in New Hampshire, however, and is now just 4 points behind Romney. Thompson is third in Iowa and fourth in New Hampshire, though he’s running even with Giuliani in South Carolina.

What’s amazing is that, for all his attractive qualities — brains, good looks, executive experience — Romney cannot seem to cut it in the national polls, falling to fourth in recent surveys and barely breaking single digits.

One Republican consultant I talked to diagnosed “an authenticity issue with Romney that you don’t see with Giuliani or McCain” based on his changing positions to appeal to social conservatives.

This consultant quoted an aerospace executive he encountered who said that “Romney is a businessman and businessmen are all about increasing market share. If you want to do that, you often do it by redesigning the product. That doesn’t always work in politics.”

At the same time, Giuliani has serious problems with the religious right, whose leaders have declared they might bolt from the GOP if he is nominated because of his pro-abortion-rights stance.

The depth of feeling was illustrated by Richard Land of the Southern Baptist Convention, who said, when I asked about Giuliani’s pledge to appoint conservative judges, “It wouldn’t cut it with a never-divorced man.

“For a man who promised two wives that he would love, honor and cherish them till death do us part, it cuts even less ice,” he said, referring to Giuliani’s divorces.

On the other hand, as several Republican activists declared, there is one cementing force that will hold the GOP together: the prospect of Clinton as president. And that prospect is real. At the moment, she leads Giuliani by 5.5 points in polling averages, Thompson by 10.7 and Romney by 11.7.