"America, now is not the time for small plans," the 47-year-old Illinois senator told an estimated 84,000 people packed into Denver's Invesco Field, a huge football stadium at the base of the Rocky Mountains. (Obama's Speech:
He vowed to cut taxes for nearly all working-class families, end the war in Iraq and break America's dependence on Mideast oil within a decade. By contrast, he said, " has voted with President Bush 90 percent of the time," a scathing indictment of his Republican rival - on health care, education, the economy and more.
"Sen. McCain likes to talk about judgment, but really, what does it say about your judgment when you think George Bush was right more than 90 percent of the time?"
He said it's time to change leadership in Washington after two terms of the Bush administration. "On Nov. 4," he said, "we must stand up and say: Eight is enough."
"Obama took sky-high expectations and brought them down to ground level with a tremendous political speech that tried to connect with the concerns of average American voters," said CBSNews.com senior political editor Vaughn Ververs. "He managed to mix boiler-plate policy proposals with American stories and values into a road map for the fall campaign. It will take a few days before we know whether voters think Obama hit a home run here in Denver tonight, but by any measure, it was a big success." ( )
"I think it was a fine speech," said CBS News chief Washington correspondent Bob Schieffer. "He made the argument that he is qualified to be commander-in-chief - which is one of the criticisms that has been made against him - because of his judgment, not his experience. And, again, he questioned John McCain's judgment. But if this speech is successful for him, it will be because he got through to people who are worried about their kids' education, who are worried about whether they're going to have health care and he talked a lot about that."
Obama repeatedly tried to link McCain to Mr. Bush.
"For over two decades, he's subscribed to that old, discredited Republican philosophy - give more and more to those with the most and hope that prosperity trickles down to everyone else," Obama said. "In Washington, they call this the Ownership Society, but what it really means is, you're on your own. Out of work? Tough luck. No health care? The market will fix it. Born into poverty? Pull yourself up by your own bootstraps - even if you don't have boots. You're on your own."
"Well it's time for them to own their failure," he added. "It's time for us to change America."
Polls indicate a close race between Obama and McCain, the Arizona senator who stands between him and a place in history. On a night 45 years after Martin Luther King Jr. delivered his "I have a Dream Speech," Obama made no overt mention of his own race.
"I realize that I am not the likeliest candidate for this office. I don't fit the typical pedigree" of a presidential candidate. That was as close as he came to the long-smoldering issue that may well determine the outcome of the election.
Fireworks lit the night sky as Obama accepted the cheers of his supporters. His wife, Michelle, and their daughters Malia and Sasha joined him, and the country music sounds of "Only in America" filled the stadium.
Campaigning as an advocate of a new kind of politics, he suggested at least some common ground was possible on abortion, gun control, immigration and gay marriage.
Obama delivered his 44-minute nominating acceptance speech in an unrivaled convention setting, before a crowd of unrivaled size - the filled stadium, the camera flashes in the night, the made-for-television backdrop that suggested the White House, and the thousands of convention delegates seated around the podium in an enormous semicircle.
Obama and his running mate, Sen. of Delaware, leave their convention city on Friday for Pennsylvania, first stop on an eight-week sprint to Election Day.
Rep. John Lewis of Georgia spoke from the convention stage of the anniversary of King's memorable speech.
"Tonight we are gathered here in this magnificent stadium in Denver because we still have a dream," said the Georgia lawmaker, who marched with King, supported Obama's primary rival, Hillary Rodham Clinton, then switched under pressure from younger black leaders in his home state and elsewhere.
Obama's aides were interested in a different historical parallel from King - Obama was the first to deliver an outdoor convention acceptance speech since John F. Kennedy did so at the Los Angeles Coliseum in 1960.
In his speech, Obama pledged to jettison Mr. Bush's economic policy, and replace it with his own designed to help hard-pressed families.
"I will cut taxes for 95 percent of all working families. Because in an economy like this, the last thing we should do is raise taxes on the middle class," he said.
The speech didn't mention it, but Obama has called for raising taxes on upper-income Americans to help pay for expanded health care and other domestic programs.