CHICAGO, Illinois (CNN) -- Democratic White House hopeful Sen. Barack Obama told CNN on Tuesday his early opposition to the Iraq war proves he has the judgment to lead the country out of the conflict.
The Illinois Democrat also said polls show that voters think rival Sen. Hillary Clinton would be better at ending the war because the New York Democrat has blurred the distinctions between the two candidates.
"Everybody had difficult choices to make, and these were difficult choices. I made the right choice, and I think that's relevant not to the past, but to the future," Obama said in an interview with CNN's Candy Crowley of his decision as an Illinois state senator to come out against the war in 2002.
In a speech at that time, five months before the U.S. invaded Iraq, Obama said publicly that Iraqi leader Saddam Hussein "poses no imminent and direct threat to the United States, or to his neighbors," that he could be contained, and that "even a successful war against Iraq will require U.S. occupation of undetermined length, at undetermined cost, with undetermined consequences."
Obama added that such a war would "strengthen the recruitment arm of al Qaeda."
On Tuesday, in a speech in Chicago, Obama reflected on his early opposition.
"In this campaign, we've seen who has the leadership to lead the country during difficult times -- I did not only oppose the war but laid out reasons that turned out to be prescient over time, and I think that says something about my judgment," he said.
Obama questioned the judgment of lawmakers who voted to authorize the war -- which includes his two top rivals for the Democratic nomination, Clinton and former Sen. John Edwards. Watch Obama call Iraq 'one big mistake.' »
"This was a vote about whether or not to go to war," the Democratic presidential candidate said. "That's the truth as we all understood it then, and as we need to understand it now. And we need to ask those who voted for the war: How can you give the president a blank check and then act surprised when he cashes it?"
Of the Democratic presidential candidates who served in Congress during the October 2002 vote to authorize force in Iraq, only Ohio Rep. Dennis Kucinich voted no.
Asked why his early opposition isn't resonating with more Democratic primary voters, Obama said Clinton has been successful in obscuring the differences between their two records on this issue.
"It's our job to make these distinctions clear to the American people, because it really ends up speaking to how we're going to make decisions in the future and how we're going to make decisions about a series of significant threats and how we are going to make decisions about getting out of Iraq."
Obama also said he is not discouraged by recent polls that indicate he significantly trails Clinton, saying Americans are just beginning to pay attention to the race.
"You know, I recognize that there has been a sense that this campaign has been lasting in perpetuity, but the American people are just starting to focus," he said. "We just went up for the first time in New Hampshire on television. We've got three months of campaigning before the first Iowa caucus, and then we've got a number of primaries and caucuses after that. So we feel very comfortable with the pace that we're on." E-mail to a friend
CNN's Alexander Mooney and Lauren Kornreich contributed to this report.