Barack Obama: 'I Accept Your Nomination for the Presidency of the United States'

Obama Marks Sharp Contrasts With John McCain

In his Democratic nomination acceptance speech, Obama sharply contrasted his candidacy with Arizona Sen. John McCain, mentioning his Republican rival about 21 times.

"John McCain has voted with George Bush ninety percent of the time," Obama said. "Senator McCain likes to talk about judgment, but really, what does it say about your judgment when you think George Bush was right more than ninety percent of the time? I don't know about you, but I'm not ready to take a ten percent chance on change."

Rumors swirled at the convention center that McCain would announce his vice presidential candidate tonight.

However ABC News' George Stephanopoulos reports a senior campaign official said, "There will be no announcement tonight. There will be no leak tonight. This is Barack Obama's night. His nomination is a singular achievement. Tonight's his night to make his case."

Obama to Make 'Commander-in-Chief' Case

Obama aggressively argued that an Obama White House would keep Americans safe. It's a weak spot for Obama, with the latest ABC News/Washington Post poll showed McCain leading Obama by 2-1 margins as more knowledgeable on world affairs and as better-suited to be Commander-in-Chief.

Taking the fight to McCain, Obama aggressively attacked the GOP nominee, and defended Democrats' ability to keep the nation safe.

"John McCain likes to say he'd follow Osama bin Laden to the gates of hell. But he won't even follow him to the caves he lives in," Obama said.

"We are the party of Roosevelt. We are the party of Kennedy. So don't tell me that Democrats won't defend this country," Obama said. "Don't tell me that Democrats won't keep us safe. The Bush-McCain foreign policy has squandered the legacy that generations of Americans -- Democrats and Republicans -- have built, and we are to restore that legacy."

"As Commander-in-Chief, I will never hesitate to defend this nation, but I will only send our troops into harm's way with a clear mission and a sacred commitment to give them the equipment they need in battle and the care and benefits they deserve when they come home," he said.

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Obama also pledged to "end this war in Iraq responsibly, and finish the fight against al Qaeda and the Taliban in Afghanistan" -- using softer language than his calls for "immediate" withdrawal of US troops in Iraq at the beginning of his campaign.

Obama ended his speech with a rousing request for people to vote for him in November.

"America, we cannot turn back. Not with so much work to be done. Not with so many children to educate, and so many veterans to care for. Not with an economy to fix and cities to rebuild and farms to save. Not with so many families to protect and so many lives to mend. America, we cannot turn back. We cannot walk alone. At this moment, in this election, we must pledge once more to march into the future. Let us keep that promise -- that American promise -- and in the words of Scripture hold firmly, without wavering, to the hope that we confess. Thank you, God Bless you, and God Bless the United States of America."

Fireworks went off at the end of his speech red and blue star shaped confetti fell.

Obama was joined on stage by his wife Michelle Obama, their daughters Mailia, 10, and Sasha, 7, and his vice presidential candidate Joe Biden and his wife Jill.

Michelle Obama Didn't See Draft

Despite the Martin Luther King anniversary, Michelle Obama told ABC's Charlie Gibson in an interview that aired on World News Thursday that the speech would be be geared toward all Americans.

"You know, I think that the issues that are effecting the country really transcend race and gender and age. That's what I've been finding throughout this campaign," Michelle Obama told Gibson.

"When someone is struggling to pay to put gas in their car, when a person has lost their job, and doesn't have health care, and they're worried about their kids' college education, those problems know no racial boundaries ... we're suffering these issues equally, and if we're going to fix them, we're going to have to work together."

Michelle Obama said she hasn't seen a draft of the speech and stopped her husband when he started reading it to her.

"I like to, to feel the impact like everyone else," the potential first lady told Gibson.

She sat beaming as she listened to his speach with her daughters beside her.

Sen. Hillary Clinton sat listening in a skybox, but neither her daughter Chelsea, nor her husband were with her.

She sat with Ohio Gov. Ted Strickland, New York Gov. David Paterson, former Iowa Gov. Tom Vilsack, New Jersey Gov. John Corzine, Maryland Gov. Martin O' Malley, and LA Mayor Antonio Villaragosa, and her childhood best friend Betsy Ebeling and her staff.

Al Gore: McCain Recycling Bush Policies

In an earlier speech to the packed stadium crowd, former Vice President Al Gore compared the choice in this election to the choice in 2000 when he ran against then-Gov. George W. Bush, knocking McCain for "recycling" the same old Bush-Cheney policies.

"Today, we face essentially the same choice we faced in 2000, though it may be even more obvious now, because John McCain, a man who has earned our respect on many levels, is now openly endorsing the policies of the Bush-Cheney White House and promising to actually continue them. The same policies all over again?" Gore said.

"Hey, I believe in recycling, but that's ridiculous."

"With John McCain's support, President Bush and Vice President Cheney have led our nation into one calamity after another because of their indifference to fact; their readiness to sacrifice the long term to the short term, subordinate the general good to the benefit of the few and short-circuit the rule of law."

Gore also said if he won in 2000, the nation wouldn't still be in Iraq.

"Take it from me, if it had ended differently, we would not be bogged down in Iraq, we would have pursued bin Laden until we captured him. We would not be facing a self-inflicted economic crisis; we would be fighting for middle-income families. We would not be showing contempt for the Constitution; we'd be protecting the rights of every American regardless of race, religion, disability, gender or sexual orientation. And we would not be denying the climate crisis; we'd be solving it."

Obama Camp: 'Persuasion Opportunity'

Obama spoke to the crowd on an "in the round," surrounded by the crowd and flanked by columns and a large screen.

The McCain campaign had labeled the stage on which the Democratic contender will speak the "temple of Obama," likening Obama to a rock star and continuing to criticize him as a celebrity rather than a serious candidate for the White House.

Senior Obama campaign officials said the stage is "simple" and "serious" and told ABC News they are not going to apologize for what they called an "enthusiasm gap" between Obama and McCain supporters.

Obama's acceptance speech was moved from the Pepsi Center in Denver, which can accommodate about 20,000 people, to the football stadium earlier this summer.

In a clever political move, the McCain campaign released Thursday night a one-evening-only ad airing on national cable that congratulates Obama on his historic nomination.

"Sen. Obama, this is truly a good day for America," McCain says in the ad. "Too often the achievements of our opponents go unnoticed. So, I wanted to stop and say, congratulations."

"How perfect that your nomination would come on this historic day," McCain continues to say in the ad. "Tomorrow, we'll be back at it. But tonight, senator, job well done."

Obama's campaign said 80,000 people in 48 hours had requested a ticket to Thursday's event and they claim they turned away tens of thousands of people to make space for delegates and other leaders.

A majority of the packed stadium -- 65 percent of the people -- were from the Southwest region including Colorado, Nevada and New Mexico -- states thought to be in play for either Democrats or Republicans in November.

Millions more watched from home and online with Obama scheduled to speak in primetime. Jennifer Hudson sang the national anthem and Sheryl Crow and Stevie Wonder performed.

Viewing the speech as a "persuasion opportunity" to reach out to independent voters in Colorado, the campaign put some of the tens of thousands of people in the stands to work -- calling voters, texting friends -- and training them how to register voters in their area.

Just around 8:00 p.m. ET Obama supporters received this text message: "Final night of convention is tonight -- don't miss Barack's speech! To get involved locally, REPLY: VOL plus your FIRST NAME and TOWN (ex: VOL Ann Chicago)."

Inside the stadium, Denver resident Sandra Bridge, 63, told ABC News, "This is the most exciting period of my life."

"Martin Luther King's dream seemed like it had slipped away," Bridge said. "The dream is real now."