The new swoon for Al Gore among some Democratic activists adds one more White House hopeful who is surely not interested in being No. 2 to Hillary Rodham Clinton, the presumed front-runner for the party’s nomination two years from now.

The once-exiled former vice president could join the 2004 Democratic team, John Kerry and John Edwards, in what would be an exclusive club: potential rivals to New York’s junior senator who would have nothing to gain against her by keeping the gloves off. Gore spent eight years in office as next-in-line; it is impossible to imagine Kerry accepting a demotion after running in the top spot; and Edwards has already played second fiddle.

So far, no one who’s making noises about running for the 2008 Democratic nomination is daring to attack Clinton. They all act like she is not there, as if they should be taken seriously without articulating why the conventional wisdom predicting her nomination is wrong.

Of course, going negative on Clinton will probably doom any chances of getting on her ticket. Even more so than her husband, Clinton is well known for a take-no-prisoners stance against political foes. So it will be interesting to see if any of the also-rans are prepared to go after her. The first to do so can join the club of serious presidential contenders.

But unless one of the newcomers, such as former Gov. Mark Warner of Virginia or Sen. Evan Bayh of Indiana, shows some inclination to openly challenge her pre-eminence, it is safe to assume that they are running mates in waiting.

That leaves Gore, Kerry and Edwards as the first tier of Clinton alternatives who have nothing to lose by running against her.

Gore is the wild card in that bunch, and while saying he has no current intention of running, he knows better than to close the door completely. The reaction to his recent turn on the national stage from liberal bloggers and elsewhere among party faithful was surprisingly positive. Starring in “An Inconvenient Truth,” his highly acclaimed documentary on global warming, and in a bit on NBC’s “Saturday Night Live,” Gore is seemingly emerging from nowhere to captivate the attention of Democrats hungry for a party hero.

Although conservatives instinctively fell into their comfort zone of attacking him as a geeky nut case, there was little of the liberals’ longtime derision of Gore as a has-been who let them down so hard by ending his protest of the 2000 presidential contest too soon. If anything, their bitterness toward him appears to have faded into an almost weepy nostalgia, encouraged by polls showing President Bush about as unpopular as a president can be.

It is almost as if Bush’s profound decline has vindicated and elevated Gore, who took full advantage of the possibilities in his comic turn on the May 13 “Saturday Night Live.” From an Oval Office mock-up, he pretended to address the nation as if he were president — and proceeded to spoof the plight of the actual sitting president in many ways. “Right now, in the second week of May 2006, we are facing perhaps the worst gas crisis in history,” he said. “We have way too much gasoline. Gas is down to 19 cents a gallon, and the oil companies are hurting.”

A silly joke, perhaps, but the hints of what could have been with Gore at the helm found a receptive audience among forlorn Democrats searching for a future that might just be hidden in their past.

Kerry could find that the back-to-the-future sentimentality for Gore does not extend to him. Memories of his inadequacies as the nominee last time remain too fresh, although he is showing signs of an emerging ability to speak directly. On a recent interview with Tim Russert on NBC’s “Meet The Press,” the Massachusetts senator uncharacteristically managed to answer a few yes-or-no questions by actually saying “yes” or “no,” although he went on to give typically long-winded explanations.

Edwards seems better positioned than Kerry to take hold in the 2008 presidential race. His incessant travels around the country are well received. Although regarded among party operatives as a disappointment on the 2004 ticket, he can make a sound case that he was bedeviled by a poorly run Kerry machine that did not know what to do with him and inexplicably wrote off the South despite picking a son of the region as running mate.

Can any of these men beat Clinton for the nomination? The trouble with Gore, Kerry and Edwards is that the best case to be made against her with Democratic primary voters is that, love her though they may, she cannot win a national general election. That is a tough case coming from three men who have recently lost national general elections.

Still, somebody must seed doubts before Clinton closes in on her rumored goal of raising $200 million for a presidential campaign. At that point, running for running mate is all the rest of the Democratic field will be able to hope for.

Contributing Editor Craig Crawford is a news analyst for MSNBC, CNBC and “The Early Show” on CBS. He can be reached at ccrawford@cq.com.