Senator Barack Obama is running for president as one of the few candidates who opposed the Iraq war from the beginning, a simple position unburdened by expressions of regret or decisions over whether to apologize for initially supporting the invasion.
Iraq remains a defining topic in the opening stages of the 2008 presidential race, but it may prove easier for Mr. Obama, Democrat of Illinois, to revisit the past than to distinguish his views in the future. The current Iraq proposals of Mr. Obama; Senator Hillary Rodham Clinton, Democrat of New York; and former Senator John Edwards of North Carolina share more similarities than differences, including a gradual withdrawal of troops.
Though Mr. Obama is framing his candidacy to appeal to Democrats who have long opposed the war, until recently he was not among his party's most outspoken voices against it. He campaigned strongly against the war in his bid for the Senate in 2004, but when he arrived in Washington he waited 11 months to deliver a major speech on Iraq.
And only after Mr. Obama opened a presidential exploratory committee did he introduce legislation to withdraw American combat brigades from Iraq by March 31, 2008.
In an interview last week, Mr. Obama said he intended to continue using the authorization of the war to distinguish himself from fellow Democratic presidential candidates. In addition to Mrs. Clinton and Mr. Edwards, Senators Christopher J. Dodd of Connecticut and Joseph R. Biden Jr. of Delaware voted to authorize the invasion.
"The authorization vote is relevant only because it gives an insight into how people think about these problems and suggests the sort of judgment they apply in evaluating a policy decision," Mr. Obama said. "There are people who sincerely believe that this was the best course of action, but in some cases politics entered into the calculation. In retrospect, a lot of people feel like they didn't ask hard enough questions."
Mr. Obama was not always so critical of the Congressional vote, taken on Oct. 11, 2002. In several interviews before the Democratic National Convention in 2004, where his national political ascent began, he said he did not place blame on Democrats who had voted to authorize the war, conceding he had not been privy to the same intelligence information.
Now, he appears intent on drawing the contrast between his early opposition to the war and the Senate votes to authorize it by Mr. Edwards, who has since repudiated his vote and apologized for it, and Mrs. Clinton, who has not apologized but has said she would not have supported the resolution had she known then what she knows now.
These days Mr. Obama dismisses the suggestion that it was easier for him to speak against the war because he was not serving in the Senate and therefore not obligated to vote on the matter. He recalled worrying, at the time, that he might lose his Senate primary election because of his decision to oppose the Iraq invasion.
"It certainly didn't look like a cost-free decision when Saddam Hussein's statue was being pulled down in Baghdad," Mr. Obama said in an interview. "I was in a hotel room in the middle of my Senate campaign, watching that happen, and President Bush's job approval rating was at 60 percent. Those who voted for the authorization felt pretty good."
In a Senate debate on Iraq last June, Mr. Obama voted to oppose an amendment seeking to set a specific timetable for withdrawing American troops. His current position on a withdrawal mirrors the conclusions of the bipartisan Iraq Study Group, which recommended a specific time frame for troops to leave.
Now the politics of the war seem to be working in his favor among Democratic primary voters.
As Mr. Obama has introduced himself in the opening weeks of his candidacy, few subjects have garnered more applause than his criticism of the war. He does not refer to the conflict as Mr. Bush's war, which antiwar candidates in the Democratic Party did in the 2004 election, but rather is seeking to expand the circle of responsibility to those who supported the invasion.
"We continue to be in a war that should never have been authorized," Mr. Obama told an audience in Iowa last week, making a not-so-subtle reference to Mrs. Clinton and other Democratic rivals. Two days later, at a Texas rally, he said, "I am proud of the fact that way back in 2002, I said that this war was a mistake."
As if on cue, the crowds of Democrats cheered with gusto.
Nolden Gentry, a lawyer in Des Moines who has been in audiences to see Mrs. Clinton and Mr. Obama in the past month, said Mr. Obama's position on Iraq was one of many factors setting his candidacy apart in the eyes of Democrats. "He's more pure on the war," Mr. Gentry said, walking from a town meeting where he and 2,200 others had seen Mr. Obama.
Sterletha Grover, an account representative for a computer company who saw Mr. Obama speak to about 20,000 people on Friday in Austin, Tex., said she liked his view on Iraq. "We shouldn't have gone there in the beginning," she said.
Mr. Obama highlights his points of distinction on the war in meetings with party officials and influential donors as well. During his trip to Des Moines last week, he met behind closed doors with members of the Iowa House of Representatives and the State Senate. In both sessions, participants said, he raised the issue of Iraq himself.
Still, his proposals for Iraq do not go as far as those of others in the Democratic field, particularly that of Representative Dennis J. Kucinich of Ohio, who voted against the Iraq authorization and has recommended cutting military spending to end the war. Mr. Edwards, too, has called on Congress to pass substantive legislation that would, among other measures, block financing for a buildup of troops. Mr. Obama has not suggested such proposals.
Among the differences in the plans offered by Mr. Obama and Mrs. Clinton is that she does not propose setting a deadline for American troops to be withdrawn. The titles of their plans, though, are similar. Hers is called the Iraq Troop Reduction and Protection Act of 2007, and his is the Iraq War De-escalation Act of 2007.
In the interview last week, Mr. Obama said that he had not wavered on Iraq since the onset of the war and that he disagreed with critics who said he had become more vocal since becoming a candidate. He said he did not deliver speeches on the topic when he first arrived in the Senate because he was taking a low-key approach in his first year in office.
"As a freshman, our objective was not to try to get in the front all the time," Mr. Obama said. "But the truth is that in that first year, we had just seen an Iraqi election, and my feeling was that while I was not optimistic, it was appropriate to try to give the nascent government a chance."
At the time, Mr. Obama was also not planning to run for president. He opened his presidential exploratory committee on Jan. 16. The next day, Mrs. Clinton presented her Iraq plan on Capitol Hill.
As he stepped into an elevator that day, reporters asked whether he would be presenting a specific Iraq proposal. "That will be coming soon," he replied. Aides went to work, formulating legislation consistent with his views from more than four years earlier. And 13 days later, on Jan. 30, his plan was introduced.