DENVER To shouts of "Yes we can," Democrats nominated Barack Obama on Wednesday as their presidential candidate in a historic first for a black American, sending him into battle against Republican John McCain.
In an emotional moment of unity, Obama's one-time opponent, Sen. Hillary Clinton, strode onto the floor of the party's national convention during a roll call of the states and formally asked Democratic delegates to suspend their count and approve his nomination by acclamation.
"With eyes firmly fixed on the future, in the spirit of unity, with the goal of victory, with faith in our party and our country, let's declare together in one voice right here, right now, that Barack Obama is our candidate and he will be our president," she said to roars of approval inside the packed convention hall.
"I move Senator Barack Obama of Illinois be selected by the convention by acclamation as the nominee of the Democratic Party," she said, a request quickly accepted by the convention's presiding official, House of Representatives Speaker Nancy Pelosi of California.
When Pelosi pounded a gavel to declare Obama the nominee, delegates held hands together up high, danced and swayed back and forth to the song "Love Train" in celebration of the moment.
"Yes we can," the crowd chanted. "Obama!"
Pelosi announced a short time later that Obama had accepted the nomination and would tell the convention that himself in his acceptance speech on Thursday night.
In honor of Clinton's tenacity in her bruising primary battle with Obama and in an effort to encourage party unity, delegates had earlier granted the symbolic gesture of nominating Clinton herself for the candidacy.
RUNNING NECK-AND-NECK IN POLLS
The nomination formally set Obama, 47, on track to face McCain in the November 4 election in a race that has been neck-and-neck for weeks, with McCain's Republican nominating convention to take place next week in the Minnesota city of St. Paul.
"No matter where we stood at the beginning of this campaign, Democrats stand together today," said Florida Democratic Rep. Debbie Wasserman Schultz in a nominating speech on behalf of Obama. She had backed Clinton's candidacy.
It was a remarkable moment for Obama, the son of a black father from Kenya and white mother from Kansas who was raised in humble beginnings and began his relatively short political career as a community organizer in Chicago.
Obama, who would be the first black U.S. president, arrived in Denver to prepare for his acceptance speech on Thursday to a crowd of about 80,000 people at the Denver Broncos' pro football stadium.
Speaking at a veterans' round-table in Billings, Montana, Obama said, "We've had a great convention so far."
"We've had two powerful women speak back-to-back on each night, Michelle Obama and Hillary Clinton," he said. Obama's wife Michelle had addressed the convention on Monday.
Clinton, who stressed her support for Obama on Tuesday night in a stirring address to the convention, released her delegates on Wednesday, freeing them to back Obama.
Before the nomination vote, Clinton spoke to a crowd of about 3,000 people, including the nearly 2,000 delegates she won.
"This has been a joy. We didn't make it, but boy did we have a good time trying," she said.
The crowd roared "No" when she told them that she was releasing them as her delegates.
"We will leave Denver united. My goal is that we win in November," she said, noting that she had cast her own vote on behalf of Obama.
Top Obama strategist David Axelrod told reporters on Obama's flight to Denver that Obama's big speech was essentially written.
"He's going to lay out a case for change. He's going to set the stakes of this election, the risks of continuing down the road we're on which is plainly what Sen. McCain is offering," Axelrod said.
(Additional reporting by John Whitesides, Caren Bohan, Thomas Ferraro, Rob Doherty and Howard Goller; editing by David Wiessler)