Surrounded by family members and friends, Obama and Biden waved to the cheering crowd in Invesco Field at Mile High as Brooks and Dunn's "Only in America" segued to the soundtrack from the football-themed movie, "Remember the Titans," to close with Bruce Springsteen's "Born in the USA."

"We all know why we're here tonight," said vice presidential candidate Biden, the U.S. senator from Delaware. "We're here for the millions of Americans who've been knocked down ... (and) to send a message that together we're going to get back up as a nation."

During his acceptance speech, Obama said the promise of America is "the idea that we are responsible for ourselves, but that we also rise or fall as one nation; the fundamental belief that I am my brother's keeper; I am my sister's keeper."

Obama, the first black major-party presidential candidate, recognized presumptive Republican nominee Sen. John McCain's patriotism and military service. But the Arizona Republican has too often supported the policies and politics of President George W. Bush, he said.

"I don't believe that Senator McCain doesn't care what's going on in the lives of Americans," he said. "I just think he doesn't know."

In adjourning the gathering, DNC permanent chairwoman, House Speaker Nancy Pelosi of California, urged delegates and others to work to elect Obama and Biden and "to make the changes America needs."