Barack Obama claimed the Democratic presidential nomination in a long-time-coming victory speech Tuesday that taunted Republicans on their own turf and reached out to heal Democratic wounds with lofty praise for his rival.
"Let us begin the work together," Obama exhorted thousands of cheering supporters in a packed sports arena. "Let us unite in common effort to chart a new course for America."
Speaking in the same arena that will host the Republican nominating convention in early September, Obama said the long, hard primary campaign, now finally ended, should help steel a deeply divided party to do more effective battle against Republicans and their candidate, John McCain.
"Senator Hillary Clinton has made history in this campaign not just because she's a woman who has done what no woman has done before, but because she's a leader who inspires millions of Americans with her strength, her courage, and her commitment to the causes that brought us here tonight," Obama said.
"Our party and our country are better off because of her, and I am a better candidate for having had the honor to compete" with her, he said.
Speculation spread over whether he would invite her to share the ticket as his running mate, and Clinton only encouraged it. But Obama aides tied to tamp down such talk.
"We don't have a long list or a short list," said David Axelrod, Obama's chief strategist. "Obviously she's an incredibly formidable person. We knew that going in. It's way too early to talk about that."
Obama won a mathematical lock on the nomination as previously undeclared superdelegates - elected and party officials - flocked to his side on the day of the last presidential primaries. Still, Clinton did not concede her own defeat.
The Illinois senator's victory rally had all the trappings of a party convention - and intentionally so.
At the Xcel Energy Center, where the GOP convention will begin Sept. 1, nearly all of the 18,000 seats taken and thousands of additional supporters gathered outside. The arena was festooned with large American flags. Loud music blared. The hall erupted into tumultuous screams and cheers when Obama and his wife, Michelle, entered. Supporters pumped Obama signs.
His long-time-coming victory speech minced no words about McCain.
"In just a few short months, the Republican Party will arrive in St. Paul with a very different agenda. They will come here to nominate John McCain, a man who has served this country heroically. ... My differences with him are not personal; they are with the policies he has proposed in this campaign."
Obama challenged McCain's claims of independence, noting he voted with President Bush 95 percent of the time last year.
"There are many words to describe John McCain's attempt to pass off his embrace of George Bush's policies as bipartisan and new," Obama said. "But change is not one of them."
Reuniting a party divided by the marathon, 17-month battle between the two historic candidates - a woman and a black man - will be a top challenge for the Illinois senator as he moves into a general election race with McCain.
"After 54 hard-fought contests, our primary season has finally come to an end," Obama said, recalling the day in February 2007 when he announced his candidacy at the Illinois Capitol and the millions who have voted since then.
"Tonight, I can stand before you and say that I will be the Democratic nominee for president of the United States," he said. That line brought down the house.
Unity and change were the main themes of his speech, as they have been on the campaign trail.
"There are independents and Republicans who understand that this election isn't just about the party in charge of Washington, it's about the need to change Washington. There are young people, and African-Americans, and Latinos, and women of all ages who have voted in numbers that have broken records and inspired a nation," he said.
Obama nailed down the nomination on a day in which the two rivals split the last two primaries, with Clinton winning South Dakota and Obama taking Montana.