Gore, who steadily has dismissed questions about his plans for 2008, created a stir when he told reporters: "I haven't completely ruled out running for president again in the future, but I don't expect to."

That slight deviation from his past denials of presidential dreams has spurred speculation that Gore might suit up again for a presidential bid, leading Sen. Barbara Boxer, D-Calif., to enthuse that it would be "fabulous" if Clinton and Gore both ran for the Democratic presidential nomination.

"The two of them are very strong candidates," she said.

Gore, 58, who won the popular vote in the 2000 presidential election but lost the White House after a blizzard of ballot recounts in Florida and Supreme Court intervention, is on the lecture circuit to talk about global warming.

His best-selling book and documentary film, An Inconvenient Truth, in which global warming is described as the greatest crisis the world has ever faced, have opened up global speaking opportunities.

John Zogby, an independent pollster with Zogby International, sees "a battle royal shaping up."

"Frankly, this is Al Gore's year and it's Al Gore's turn and that's the thing "" it's also Hillary's turn," Zogby says.

Gore is "in a very second tier after Hillary, who is in a league by herself," Zogby says. He says Clinton "really sucks the air out of the contest because she's new, she's a woman and she's Hillary "" no last name needed."

On the other hand, Gore has "two aces in the hole," Zogby said. Unlike Clinton, he opposed the Iraq war from the start. And he is known as an expert on the environment.

Clinton, who was first lady for eight years while Gore was No. 2 to her husband, praises his work on global warming, calls his film "excellent."

But when asked about a Gore candidacy in 2008, Clinton laughs and curtly moves on, saying: "You'd have to talk to him about that."

Marshall Wittmann, a senior fellow with the Progressive Policy Institute, a Democratic policy group, says Gore is "clearly and certainly leaving the door open."

Wittmann says Gore is "probably reading up on what Richard Nixon's path out of the wilderness was," in 1968 after he spent several years out of public life.

While Nixon lightened his image by appearing on the comedy show Laugh-in, Gore put the nation in stitches appearing on Saturday Night Live, in a series of skits that included impersonations of Sen. Trent Lott, R-Miss., his own refusal to leave the Oval Office and being shot with a stun gun after a long kiss with his wife, Tipper.

Courtesey Hearst News