In a deafening moment of history, Democrats on Wednesday appointed Barack Obama the first black major-party nominee for president, in a cathartic release of unity, hope and tears.
The newly-minted nominee then sent the Democratic National Convention into raptures by crashing his own party a day early, after a stemwinding speech from running-mate Joseph Biden and a belated but glowing endorsement from Bill Clinton.
Only Republican John McCain, who accepts his party's nomination next week and reportedly settled on the name of his vice presidential pick on Wednesday, can now halt Obama's historic before the White House.
Obama took his stunning political rise to new heights as former foe Hillary Clinton halted a roll-call vote and called for the 47-year-old son of a Kenyan father and white mother from Kansas to be nominated by acclamation.
In his first public appearance since his historic elevation, Obama said he was proud to have the Biden family along on a "journey to take America back" and praised the Clintons for helping to heal the wounds of a bruising primary.
Obama also defended his move to a nearby football stadium for his acceptance speech, on the 45th anniversary of Martin Luther King's "I have a dream" oration, after Republicans mocked the venue as a fresh sign of hubris.
"We want to open up this convention to make sure that everybody who wants to come can join in the party, and join in the effort to take America back."
Biden lauded Obama, after his own son Beau reduced Obama's wife Michelle to tears by praising his Dad's courage after a 1972 car wreck which killed the senator's first wife and daughter.
Biden ripped into an attack on McCain, though paid homage to his heroism as a Vietnam war prisoner.
"These times require more than a good soldier, they require a wise leader, a leader who can deliver change, the change everybody knows we need.
Earlier, as the nominating pageant played out, tears streamed down the faces of never-say-die Clinton supporters while many African-American Obama backers also gave in to their emotions on a day many thought they would never see.
"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," Clinton said.
Cheers thundered through the Denver sports arena hosting the convention as delegates chanted Obama's mantra "Yes We Can" "Yes We Can."
In the second act of the Clinton redemption show, former president Clinton offered a resounding endorsement, after harboring bitterness at his wife's defeat.
"Barack Obama is ready to lead America and restore American leadership in the world," Clinton said, his ovation from the crowd recreating his 1990s heydey.
"Barack Obama is ready to honor the oath to preserve, protect and defend the Constitution.
"Barack Obama is ready to be president of the United States."
"We prevailed in a campaign in which the Republicans said I was too young and too inexperienced to be commander-in-chief. Sound familiar?," Clinton asked.
"It didn't work in 1992, because we were on the right side of history.
"And it won't work in 2008, because Barack Obama is on the right side of history."
The Republicans meanwhile set the stage for their convention in Minnesota next week, as the Politico website reported McCain had chosen his running mate, and would inform him, or her on Thursday.
Clinton had on a previous occasion declined to say Obama was ready to lead, fueling a sense of mistrust between the two camps, which some analysts believe might have severely hampered Democratic hopes in November.
Obama repaid the compliment as he appeared on stage with Biden.
"If I'm not mistaken, Hillary Clinton rocked the house last night!
"And just in case you were wondering, I think president Bill Clinton reminded us of what it's like when you've got a president who actually puts people first," he said, pointing to the smiling former first couple.
The embrace of Obama by the Clintons was the latest step in a choreographed show of unity and reconciliation following their acrimonious primary dust-up.