It wasn't supposed to be like this.

Last October, when many Democrats in Congress supported the war resolution, they figured they'd take national security off the political agenda and change the subject to the economy.

That didn't happen. President Bush surprised Democrats by making national security the focus of the midterm campaign. And he won big.

Four Democratic presidential candidates voted for the war resolution. Rep. Dick Gephardt of Missouri led the fight for the resolution among House Democrats, while John Edwards of North Carolina, John Kerry of Massachusetts, and Joe Lieberman of Connecticut voted for it in the Senate. They figured the United States would bring down Saddam Hussein, they'd have political cover, and anti-war candidates such as former Vermont Gov. Howard Dean would fade away.

Saddam's regime is gone, but the other things didn't happen. What did happen is that Iraq became more controversial. Polls show more and more Americans turning against the war. According to Gallup, the number of Americans saying that Iraq was not worth going to war over went from 19 percent at the end of the war in April to 42 percent by late June. Among Democrats, opposition has been stronger: 33 percent opposed the war in mid-April, 63 percent in late June.

Now Bush is facing a credibility problem over Iraq. Last week, 41 percent of Americans polled by Time magazine believed that the Bush administration "deliberately misled" the country in order to gain support for the war. Polls this month by Time, Newsweek, ABC News/The Washington Post, and Gallup all show mounting criticism of Bush's leadership in the Iraq situation.

In the Time poll, for example, approval of Bush's handling of Iraq dropped 14 points—from 69 percent in mid-May to 55 percent in mid-July. Concern over Iraq, more than anything else, seems to be the prime cause of the drop in Bush's overall job rating from 63 percent in May to 55 percent in July. Bush is back to where he was before the war started in March.

If Bush is facing a credibility problem, so are the Democratic presidential candidates who supported the war. "I think those who voted in favor of the war in Iraq are on very thin ice," Dean told a CNN reporter last week. "They did not exercise their senatorial requirement to advise and consent, knowing all the facts."

Dean hasn't served in Congress and did not have to vote on the war, which he has consistently opposed. But Democrats in Congress who voted for the war now find themselves on the defensive. Lieberman and Gephardt have had to face audiences of angry Democrats in Iowa and New Hampshire. Kerry and Edwards have had to explain their views on the war again and again. The president and his advisers "assured us they had a plan," Kerry said at a press conference this month. "It is now evident they didn't have a plan."

At the same time, Dean has become Mr. I-Told-You-So. "I stood up against what this administration was doing, even when 70 percent of the American people supported the war, I believed the evidence was not there, and I refused to change my view," Dean declared in a speech to the Council on Foreign Relations in New York City last month. "As it turned out, I was right."

Last week, Dean released a statement challenging his competitors: "I seek accountability" not just from the administration, but also "from those who voted to give the president a blank check without asking the tough questions when they needed to be asked and long after it's clear how mistaken this path was for our nation."

Three polls this month all show that Dean has entered the top tier of Democratic candidates. Four candidates score in double digits when Democrats nationwide are asked their preference for their party's nomination: Lieberman (average of 14 percent support), Gephardt (12 percent), Kerry (12 percent), and Dean (10 percent). Dean is the only candidate who has been gaining support this year. The others have either held steady or, in the case of Lieberman and Edwards, lost support.

What do Democrats see in Dean? A Democrat who will not be cowed by Bush. "The only way to beat George Bush is to stand up to him," Dean says in an ad running in Iowa. Asked what he liked about Dean at a Dean "meet-up" in Los Angeles on July 2, supporter Phil Devillis, a cable company employee, said, "He is really well poised to take on President Bush. He won't let him get away with stuff in debates. He would be very tough on him."

Supporters also see Dean as a Democrat who will lead. "Too many Democrats in Washington are afraid to stand up for what we believe in," Dean says in another ad. Supporter Lou Cutell, an actor who appeared on Seinfeld, said, "The others who are running, like Kerry and Graham and a lot of them, they can't fight like this man can fight."

The original script for the 2004 campaign said the United States would win the war in Iraq; the war issue would fade away; and Dean and other anti-war Democrats would disappear. But the war is becoming more and more controversial. Dean is thriving. And a lot of his Democratic rivals are frantically trying to rewrite the script.

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