Democratic presidential candidate Joe Lieberman (search) unleashed a torrent of attacks Wednesday, but this time, not all were directed at President Bush.

Much of the Connecticut senator's ire was aimed at his top rivals.

"The anti-tax-cut, soft-on-defense, big-spending Democrats will take the Democratic Party to the edge and maybe over," Lieberman told Fox News while campaigning at a state-of-the-art job training center in Phoenix (search).

Though all smiles at the campaign event, Lieberman is trailing in the polls and fighting for survival.

A centrist in an increasingly liberal party, Lieberman defends his support for war against Iraq, and calls the anti-war rhetoric of his opponent, former Vermont Gov. Howard Dean (search), as the talk of an unelectable dove.

"I don't believe the American people are going to elect for president in 2004, post 9/11, in an unsettled world, a candidate who has been opposed to the use of military power against a brutal dictator like Saddam Hussein," he said.

In the past week, several of Bush's detractors have joined Dean on the offensive, accusing the president of misleading the public with intelligence that his own agencies say was not up to snuff.

On Tuesday, Missouri Rep. Dick Gephardt (search), who sponsored the Iraq war resolution in the House of Representatives while minority leader last year, joined the barrage, accusing Bush of "chest-beating unilateralism" and Republicans of "machismo."

But Lieberman says some of those detractors, including his opponents Gephardt, Massachusetts Sen. John Kerry (search), and to a lesser extent North Carolina Sen. John Edwards (search), are hypocritical for first backing the war but later complaining about it.

Lieberman himself faults Bush with not gaining enough international support to finish the job of bringing freedom to Iraq, but he said his opponents' accusations discredit only themselves.

"When you constantly criticize the war, even after it's over, even after the world is so much safer with Saddam Hussein gone and the people of Iraq have a chance for a better life, you send a message of softness on defense," he said.

Lieberman, who helped found the policy-oriented, moderately-thrusted Democratic Leadership Council (search) with former President Bill Clinton and former Vice President Al Gore, considers his candidacy an epic fight to keep his party from a self-destructive lurch leftward, and calls the Democratic race a "struggle for the heart and soul of the Democratic Party."

To that end, he also maintains his centrist credentials on the economy, for which he ripped Dean and Gephardt for promising to repeal the Bush tax cuts.

"Some of my opponents in the Democratic primaries oppose all tax cuts, would repeal all Bush tax cuts. I don't. I believe some tax cuts are an important tool of fiscal policy to get the economy going again," he said.

Lieberman did leave room for an attack on the president, saying Bush has done nothing to stop the bleeding of manufacturing jobs.

But he also slighted Kerry, Gephardt and Edwards on health care and energy issues, saying their ideas are too liberal and out-of-date.

"Some of my opponents have big spending answers to big social problems. That's old stuff. It's not going to work," he said.

While some wonder if Lieberman is Republican-light, one Democratic source familiar with the senator's philosophy said he is "progressive in almost every sense of the word as it is traditionally used."

The source said Lieberman uses language that a lot of conservative voters can understand, and that will make him more appealing in the general election. But it may take a year for his candidacy to resonate with Democratic primary voters.

"Many Democratic voters are angry at President Bush. Bush promised to change the tone in Washington, but he is almost nakedly partisan," the source said, adding that Bush's "representations, you could almost say lies" used to persuade Americans to go to war has angered many Democrats.

"What's resonating right now with Democrats is anger" like Dean's, the source said.

But Arizona may be the best place for Lieberman's pointed attacks. Though an early primary state, Arizona contains only 10 electoral votes. In the 2000 election, Bush and Vice President Cheney won the election. In 2002, Democrat Janet Napolitano took the governor's seat.

The state's Democratic Party chairman warns that the liberal tendencies emerging from New Hampshire and Iowa's primary voters could hurt the national party.

"We don't want to get stuck in an ideological corner. And I think that's the danger somewhat in New Hampshire and Iowa -- that sometimes the nominee has to appeal to that narrow slice of our party, and even narrower slice of the national voting population, in order to win those states," said chairman Jim Peterson.

Fox News' Carl Cameron contributed to this report.