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At the first full-fledged Democratic presidential debate of the campaign season, four of the eight candidates agreed that the United States is in a "global War on Terror."

Sens. Hillary Clinton, Barack Obama, Chris Dodd and New Mexico Gov. Bill Richardson all raised their hands in assent to the question posed during Thursday night's debate at South Carolina State University, though Dodd and former Sen. John Edwards also called their initial vote for the war in Iraq a "mistake."

"I was wrong to vote for this war. Unfortunately, I'll have to live with that forever. And the lesson I learned from it is to put more faith in my own judgment," Edwards said.

Clinton, Obama and Edwards, the top three Democratic presidential candidates, all said they support the congressional confrontation with President Bush over a timeline to withdraw U.S. combat forces from Iraq this year. Clinton, Dodd, Obama and Sen. Joe Biden, the other presidential hopeful on stage, all voted earlier in the day to withdraw troops from Iraq by March 31, 2008.

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"The American people have spoken. The Congress has voted, as of today, to end this war. And now we can only hope that the president will listen. I'm very proud of the Congress ... for putting together a piece of legislation which says we will fund our troops and protect them, we will limit the number of days that they can be deployed, and we will start to bring them home," Clinton said.

But distinguishing herself from the others, Clinton declined to apologize for her vote to authorize the Iraq war, a sticking point for some anti-war Democrats and a potential explanation for some recent softening of her national poll numbers.

Richardson, a challenger trying to break into the top tier, went further than the congressional action approved Thursday calling for a complete withdrawal by March 31, 2008.

A party centrist who does not have to defend any congressional vote on the Iraq war, Richardson said he wants Congress to de-authorize the war and wants “no residual U.S. force” in Iraq after the end of this year.

If he were elected president, "the first day I would get us out of Iraq by diplomacy," Richardson said.

In an exchange that may resonate as the campaign continues, both Obama and Edwards declined to endorse military retaliation for a hypothetical simultaneous attack on two American cities that the United States knows Al Qaeda perpetrated. The two said they would analyze U.S. intelligence and homeland security failures first and while they did not absolutely rule out military retaliation, their answers looked inward. Obama said he would “potentially take some action” against Al Qaeda. Edwards said “there are more tools than bombs.”

In contrast, Clinton and Richardson identified a military response as the first consideration after such an attack — Clinton more bluntly than Richardson, saying at such a time a president should “swiftly retaliate.”

The 90-minute debate comes nine months before the first in the nation vote for the parties' 2008 presidential nominees. Republican candidates have their first debate next Thursday. None of the Democrats participating Thursday night were permitted opening or closing statements and a ground rule limited answers to 60 seconds without chance for follow-up.

The candidates did not go after one another directly and the only oblique attack came from Edwards who said “generalities and high-fallutin' rhetoric” were not enough to win the White House. The statement was a jab at Clinton and Obama both of whom the Edwards campaign regards as less-substantive on issues such as poverty, health care and energy.

On economic issues, Edwards called for raising taxes on Americans who earn more than $200,000 and using the revenue to finance improvements in health care and energy efficiency. He said a national health care plan should allow private and government-backed insurance, chronic care, parity for mental health sufferers and “no pre-existing conditions” to deny coverage.

Richardson said he hoped Democrats “always do not think of new taxes to pay for new programs.” On broad economic issues, Clinton said as president she would be “a Democrat who will set the rules to begin to repair the damage” that President Bush and the previous Republican congresses inflicted on the economy.

Edwards said when he grew up in South Carolina, his father, a textile worker, sometimes could not afford to take the family to a decent restaurant — an experience, he claims keeps him connected to the needs of the middle class and poor.

Asked then to explain why he charged his campaign for a $400 haircut, Edwards said, “That was a mistake and if the question is do I live a privileged and blessed life, the answer is yes.”

Describing their most memorable mistakes in politics, Clinton cited her health care plan during her husband’s first term as president and her backing of the Iraq war; Obama said not trying to stop congressional involvement in the Terry Schiavo right-to-die fight; Biden checked off “overestimating the competence of the Bush administration and underestimating its arrogance”; Edwards and Dodd both said voting for the war; Richardson said trying “to ram through” a minimum wage increase in New Mexico.

Richardson also admitted he delayed calling for Attorney General Alberto Gonzales' resignation because Gonzales is Hispanic. Richardson said he knew Gonzales personally and didn't want to judge a fellow Hispanic too harshly until Gonzales' Senate testimony. Richardson, like many Democrats and Republicans, said the attorney general's answers didn't explain his role or motives in the firing of eight U.S. attorneys last year.

Former Alaska Sen. Mike Gravel and Rep. Dennis Kucinich of Ohio also participated in the debate. They were two of the five — along with Biden, Dodd and Richardson — who raised their hands when asked whether they had ever had a gun in their home.

Kucinich said he would nominate judges to the federal bench who "reflect my thinking." He did not mention that he opposed abortion rights until switching positions before he ran for the White House in 2004.

Biden said he thought the Supreme Court's decision to uphold a ban on partial birth abortions "was intellectually dishonest. I think it is a rare procedure that should only be available when the woman's life and health is at stake. But, what this court did is it took that decision and ... through dishonest reasoning, laid the groundwork for undoing Roe v. Wade."

Afterward, advisers said Obama met the substantive standard on a range of issues but maintained his Washington, D.C., outsider status by emphasizing a willingness to work across party lines.

But Obama's advisers acknowledged the candidate's answer to the question about Al Qaeda sponsoring simultaneous attacks left room for improvement.

"He was trying to answer two questions," said David Axelrod, a senior Obama adviser. "He wanted to emphasize the need to care for the victims, find out about intelligence failures and then try to see if we could find out for sure who attacked us, if they could be found, and decide how to proceed."

In what may be a lasting "values" image from the debate, Axelrod made note of the three frontrunners who kept their hands down on the question of gun ownership.

"We're in South Carolina, so you know all three told the truth and didn't pander" to voters who hold bipartisan enthusiasm for firearms in this rural, culturally conservative state.

Overall, Axelrod said he "felt very good" about Obama's answer and his overall performance.

Richardson adviser Steve Murphy said the governor "established himself as the most experienced foreign policy candidate and the one with the most aggressive plan to exit Iraq."

"Everyone else is for staying until next year, but we want out this year," Murphy said.

Majority Whip James Clyburn, the highest ranking South Carolinian in the House, said all the candidates "did themselves proud," but he was particularly impressed with Biden.

"I think Biden took some risks tonight and he did himself well; (I was) surprised Dodd didn't do that and Richardson didn't really," he said.

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The Associated Press contributed to this report.