Democrats open their national convention Monday to formally nominate Barack Obama for president, but the party's unity theme faces a dangerous challenge from a key constituency — the one-quarter of Sen. Hillary Rodham Clinton's backers still angry she lost and who vow not to vote for the party standard-bearer in November.
While Clinton has thrown her support to her Senate colleague from Illinois and plans to release her delegates to Obama after she speaks Tuesday night, a new USA Today/Gallup Poll shows 30 percent of her supporters across the country will vote for Republican John McCain, a third-party candidate or no one.
Convention planners have called on more than 30 party notables, many of them politicians from Obama's home state of Illinois, to rev up the four-day marathon of Democratic unity on Monday night, the opening acts for Michelle Obama — who will tell the story of what could be the first African American family to move into the White House.
Ailing Sen. Edward M. Kennedy, who is being treated for a malignant brain tumor, traveled to Denver late Sunday and was expected to attend the Monday evening festivities, according to officials speaking on condition of anonymity because no announcement had been made. A video tribute had been planned because the the beloved party figure hadn't been expected to be able to travel to the convention.
Former President Jimmy Carter will take the stage as well in a highly orchestrated first night — the symbolic opening of the two-month fall campaign
If recent polls are correct, Obama needs a major bump in support coming out of Denver. (Some Democratic super delegates could still vote for Clinton — watch the video at left.) The numbers have him running nearly even with Republican John McCain, whose party throws its own political festival next week in St. Paul, Minnesota.
McCain, a senator for more than 20 years and a Vietnam prisoner of war, showed no signs of stepping aside while the Democrats celebrate Obama. He fired off two television ads over the weekend aimed to stir discord over Obama's choice of Sen. Joe Biden as a running mate.
Biden barely had time to digest his new status before McCain — who initially called him a "wise selection" and a friend from their long Senate association — put his ad men to work on two commercials raising doubts about Biden's selection.
The most recent, launched Sunday, includes video of Clinton issuing critical remarks about Obama during their primary battle. In one clip she says, "Senator Obama's campaign has become increasingly negative."
Then an announcer says: "She won millions of votes but isn't on the ticket. Why? For speaking the truth."
Clinton spokeswoman Kathleen Strand responded that the New York senator's "support of Barack Obama is clear. She has said repeatedly that Barack Obama and she share a commitment to changing the direction of the country, getting us out of Iraq and expanding access to health care. John McCain doesn't. It's interesting how those remarks didn't make it into his ad."
Clinton, hoping to unite the Democratic Party and cement her future in it, will gather her hard-won primary delegates Wednesday at a reception where she is expected to formally release them to Obama, but recent polling shows nearly a quarter of her supporters across the country will not follow her lead in voting booths on Nov. 4.
Obama's campaign dismissed concerns about the impact of die-hard Clinton supporters.
"There are a lot of delegates here who had passionate choices in an extended primary season," Obama spokesman Robert Gibbs said on NBC television Monday morning. "We feel confidant that if we can demonstrate a record of change, a record of vision ... a team of Barack Obama and Joe Biden can convince Democrats, Republicans and independents to support a ticket of change in November."
Whether trying to counter the new McCain attacks or simply pumping up his choice for No. 2, Obama sought to further burnish Biden's credentials and character while campaigning Sunday in the battleground state of Wisconsin.
Obama said he was "absolutely convinced" Biden was right for the job.
"He's got the passion to lift up middle-class Americans, he hasn't forgotten his working-class roots, he has the expertise that will make him a great counselor on international crises that might come up," Obama told reporters before boarding his plane in Eau Claire, Wisconsin.
In choosing Biden and his matchless foreign policy expertise accumulated during a 35-year Senate career, Obama got what he may need most — a vice presidential candidate with encyclopedic foreign policy know-how and a political brawler ready to take on McCain's frontal assault on his opponent's newness on the national stage.
Obama was not yet in Denver, but was slowly making his way there on a tour of battleground states. On Monday he was scheduled to campaign in Iowa.
The candidate closes the convention Thursday night when the action shifts to a football stadium, where the 47-year-old, first-term senator will give his speech accepting the nomination. Obama said Sunday he was "still tooling around with my speech a little bit."
Meanwhile, the Democrats' credentials committee by unanimous vote has restored full voting rights to delegates from Florida and Michigan. The party had stripped both states of their voting rights for holding primaries before the rules said they could. The committee vote was taken at Obama's behest, and Democrats hope the goodwill gesture will help improve their standing in two important states.
McCain, meanwhile, wasn't disappearing from the campaign trail entirely. He was using an appearance Monday on a popular late night television talk-show program and newspaper interviews to stay in touch with voters. There is continued interest in his choice of a running mate, which he is expected to announce shortly after the Democratic convention wraps up.
Obama also released a new television ad Monday designed to link McCain to the unpopular President George W. Bush. It shows still photos of McCain and Bush together with a vocalist singing lyrics put to the tune of the old Sam Cooke song "Wonderful World."
"I'm not up on the economy. Don't know much about industry. Really can't explain the price of gas, or what has happened to the middle class.
But I know that one and one is two. And if I could be just like you, What a wonderful world this would be," the commercial says.
Associated Press writer Darlene Superville contributed to this report.