Democratic presidential candidates ganged up on front-runner Howard Dean in Tuesday night's debate, the last one before the primary cycle begins next month.

Much of their fire was directed at former Vice President Al Gore, who endorsed Dean on Tuesday.

Hoping to take the luster off Gore's endorsement, the other contenders trotted out their usual criticism of Dean's policies — or lack thereof — and suggested that the ex-veep's support of the ex-Vermont governor was old-style party-machine politics.

"We're not going to have a coronation," snapped Sen. John Edwards (search) of North Carolina.

"To quote another former Democratic leader, I think elections are about people, not about the powerful," added retired Gen. Wesley Clark (search). "I think it was Al Gore who said that."

Dean fired back, "If you guys are upset that Al Gore is endorsing me, attack me, don't attack Al Gore.

"I don't think he deserves to be attacked by anybody up here," Dean added. "He doesn't; he's not a boss. He's a fundamentally decent human being. We share a lot of values."

The debate came only weeks before Iowa's Jan. 19 caucuses and New Hampshire's Jan. 27 primary.

Advisers said Dean had welcomed the opportunity to defend Gore, who won the 2000 presidential popular vote but lost the disputed electoral contest in what many Democrats believe was a stolen election.

Better yet for Dean, criticism of Gore's endorsement left room for few attacks on his policies or campaign missteps.

"It was not the pile-on that Dean expected," said Donna Brazile, a former Gore adviser not tied to any current candidate. "Dean came with his best Teflon suit, but he didn't need it."

Critics asked why Gore threw his political weight behind a candidate whose views weren't in line with his own, and said he insulted Sen. Joe Lieberman (search), D-Conn., his 2000 running mate.

Lieberman said he only learned of Gore's Dean endorsement when the story broke Monday afternoon.

The Dean campaign claimed that Gore had wanted to notify other candidates before the planned surprise endorsement, and had called Lieberman several times on Monday, but got no response. 

"For me, Al Gore made his choice," Lieberman told Fox News on Wednesday. "I'm going forward and this is really a battle for whether the Democratic Party is going to move forward or backward."

Asked whether Dean would take the country too far to the left and might be too extreme to beat Bush, Lieberman responded: "I'm not going to stand by and let the party go in the direction I not only think is wrong for the party but wrong for the country."

The leftward movement concerns many party observers.

"The Democratic Party is lurching to the left, the tail is no longer wagging the dog — the tail has now taken over the dog," said Dick Morris, a Fox News political analyst and former Clinton administration adviser. "It's a very left-wing party."

Endorsing Dean gives Gore more traction for the future, Morris added.

"This puts him [Gore] squarely back in the running for 2008," Morris said. "Dean's not going to win — he'll win the nomination, but he won't win the election."

During Tuesday's debate, the other eight candidates were left arguing for their own relevancy.

"This race is not over," declared Sen. John Kerry (search) of Massachusetts.

One of the debate's moderators, ABC's Ted Koppel, opened the session by inviting all nine candidates to "raise your hand if you believe that Governor Dean can beat George Bush."

Only one — Dean — raised his hand.

Lieberman asserted that "my chances have actually increased today," adding that people had stopped him in the airport to express outrage over Gore's endorsement.

Calling himself a champion of the moderate, fiscally conservative, tough-on-security wing of the Democratic Party, Lieberman said, "Howard Dean — and now, I guess, Al Gore — are on the wrong side of those issues."

Rev. Al Sharpton (search) said Gore's tactics smacked of "bossism," and added: "We're not going to have any big name come in now and tell us the field should be limited. ... No Democrat should shut us up today."

Rep. Dick Gephardt (search) of Missouri declared, "I'm sure all of us think we have the best chance to beat George Bush"  — then added that his Midwestern background gave him an advantage in the crucial central "battleground" states.

One of the longer shots, Rep. Dennis Kucinich (search) of Ohio, took exception to Koppel's questions and used them to challenge the political status quo.

"I want the American people to see where media takes politics in this country," Kucinich said to cheers from the crowd. "We start talking about endorsements — now we're talking about polls and then talking about money. When you do that, you don't have to talk about what's important to the American people."

Dean was asked about his comments questioning what Bush knew of terrorist plans before the Sept. 11 attacks. Republicans have criticized him for mentioning in broadcast interviews speculations that Bush may have been tipped off, perhaps by the Saudis.

Dean insisted he never believed such reports, and had only been mentioning "the most interesting theory that I heard, which I did not believe, [which] was that the Saudis had tipped him off."

Still, Dean added, "We need to know what went wrong before 9/11. ... There are going to be a lot of crazy theories."

The Associated Press contributed to this report.