If you want to know how John McCain will run for president in 2008, just watch Joe Lieberman’s campaign this fall as an independent candidate in Connecticut’s three-way Senate race.

There will be a lot of similarities in the strategy, rhetoric and even some personnel between the two, although because McCain and Lieberman come from different political parties it is an inexact comparison.

Three-term Democratic Sen. Lieberman, his party’s 2000 vice-presidential candidate, lost an August primary to Ned Lamont. Lamont ran a stridently partisan campaign, capitalizing on resentment among Democratic activists to Lieberman’s support of President Bush’s Iraq War policy, and working relationship with the president.

McCain is an early favorite for the 2008 GOP presidential nomination. He has provoked antagonism from some in his party who view him as not partisan and conservative enough. And he will need to appeal to the GOP’s conservative base in the primaries to get nominated.

But if he does win the nomination, McCain’s general election campaign would likely look a lot like Lieberman’s.

And that would represent a change from 2000 and 2004 when Bush and Democratic opponents Al Gore and John Kerry focused more on turning out their partisans than trying to woo voters in the center.

A recent Quinnipiac University poll found Lieberman ahead of Lamont by double digits, with GOP nominee Alan Schlesinger not a serious contender. There are relatively few undecided voters left who could give Lamont victory, and most Lieberman supporters say they are unlikely to change their minds.

Lieberman’s bet that Democratic primary voters are out of step with the much larger group that votes in November seems to be paying off. History – the fact Democrats have lost seven of the past 10 presidential elections – only gives credence to his rationale.

And Lieberman’s success so far offers hope for McCain’s undeclared 2008 candidacy. That’s because although both men have supported their party leaders more often than not, neither toes the party line. This has led both to alienate the more ideologically based voters within their respective parties.

McCain, for instance, was the force behind the campaign finance reform bill that conservatives hate. He also split with the president over the treatment of prisoners in U.S. military custody and forced Bush to compromise on recent legislation on the subject.

Lieberman has not only backed Bush on the war, but is much more socially conservative than many in his party and does not always see eye-to-eye with Democratic interest groups and activists.

When Lieberman accepted defeat on primary night, he made clear that he would aim his November campaign at those who see Washington, D.C., as a captive of overly partisan politicians.

And his campaign has stuck to that theme. He has cast himself as a problem solver, not a partisan ideologue, boasting of his ability to work with both Democrats and Republicans to get things done for Connecticut, regardless of politics.

McCain’s political modus operandi has been to appeal to the center, and it is quite likely that will be the case in 2008, when many Democrats fear him as a very formidable foe if he can make it through the Republican primary process.

The similarity in approach is hardly coincidental. The two men are friends. There has been behind-the-scenes help from McCain supporters for Lieberman, and some public help also.

Lamont’s primary victory would seem to be evidence that the Democratic Party, at least in Connecticut, is rejecting the idea of moderating its image.

What we will see there come November is just how appealing the McCain/Lieberman approach will be to the vast majority who don’t vote in primaries. Because Connecticut is a true blue state, if it works, get used to the approach from McCain in 2008.