Sen. Joe Biden made his long-expected official entry into the presidential race Wednesday and immediately faced question about the personal observations he made about his Democratic rivals.

The six-term Delaware lawmaker, who has said for months he'd be a candidate in 2008, filed papers Wednesday with the Federal Election Commission to establish a campaign committee. It is the second presidential bid for Biden, who pursued the White House in 1988.

On his Web site, the Senate Foreign Relations Committee chairman devoted much of his video announcement to Iraq. But the Democrat known in Washington for his extensive thinking out loud had to deal with the fallout from his comments about Sens. Hillary Rodham Clinton and Barack Obama.

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In an interview with the New York Observer published Wednesday, Biden called Clinton's plan for stabilizing Iraq "nothing but disaster" and said of Obama: "I mean, you got the first mainstream African-American who is articulate and bright and clean and a nice-looking guy. I mean, that's a storybook, man."

Questioned about Biden's comments at a Washington news conference, Obama said: "You'd have to ask ... Senator Biden what he was thinking. I don't spend too much time worrying about what folks are talking about during a campaign season."

In the same article, Biden criticized Clinton's proposal to cap American troops and to threaten to cut funding to Iraqi security forces.

"From the part of Hillary's proposal, the part that really baffles me is, 'We're going to teach the Iraqis a lesson,"' Biden said. "We're not going to equip them? O.K. Cap our troops and withdraw support from the Iraqis? That's a real good idea."

Biden tried to play down his comments in an interview with ABC's "Good Morning America," where he praised both Obama and Clinton's candidacies.

"We have a heck of a field out there," Biden said.

In a video message posted on his new campaign Web site, www.joebiden.com, Biden criticized President Bush's conduct of the Iraq war and warned that his successor would have no margin for error in resolving the conflict.

"This administration's mishandling of the war in Iraq may be the greatest foreign policy disaster of our times," Biden said. "The next president ... is going to have to be prepared to immediately step in and act without hesitation to end our involvement in Iraq."

Biden voted in 2002 to authorize military intervention in Iraq but has since become a vocal critic of the conflict. He's also proposed a plan for peace in Iraq that would divide the country along ethnic lines.

"This is an incredibly challenging time for our country. Because in my view, President Bush has dug America into a very deep hole," Biden said.

A 34-year Senate veteran known for his foreign policy expertise, Biden also spoke of a number of domestic challenges he hoped to tackle as president, including health care, boosting job and retirement security, and tackling the threat of global warming.

"The Bush administration, because it worships profits over people, has forgotten ... we need a growing, vibrant middle class," Biden said.

Biden will transfer $3 million from his Senate account to his presidential campaign, and said he believed he needed to raise $20 million total to be competitive in next year's early primaries. Analysts believe Clinton and Obama are likely to raise $100 million each this year.

Biden was a candidate for the 1988 Democratic presidential nomination, but withdrew from the race in 1987 amid accusations that he had plagiarized passages in his speeches.

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