Barack Obama will accept the official Democratic presidential nomination at Invesco Field at Mile High, the home of the Denver Broncos football team that can accommodate more than 75,000 audience members.

Obama is set to accept the nomination with a victory speech on the night of Aug. 28, the last day of the Democratic National Convention. The date is set for Obama to become the nation's first African-American major party nominee and will mark the 45th anniversary of the "I Have A Dream" speech by the Martin Luther King, Jr.

Obama is following in the footsteps of John F. Kennedy, who in Los Angeles, Calif. accepted the Democratic nomination of the 1960s in the Memorial Coliseum. Al Gore, in an endorsement speech from June, compared Obama and Kennedy claiming that the same accusations that circulated around the young Kennedy now appear against Obama.

The Democratic National Convention Committee said Monday that the larger venue will make the convention accessible to the public in a way that has never been done before.

"When we said we wanted to 'bring down the walls,' open up this convention like never before and truly speak to the American people, we meant it," said Leah D. Daughtry, CEO of the DNCC. "On Aug. 28, we will offer grassroots Democrats, who have turned out in record numbers this year, the opportunity to witness history shoulder to shoulder with thousands of Americans standing up for the change our country desperately needs."

Howard Dean, chairman of the Democratic National Committee, said the move is symbolic of the change Obama represents.

"The Democratic Party is nominating a true change candidate this August, and it is only fitting that we make some big changes in how we put on the convention," Dean said.

The rest of the Democratic convention is being held Aug. 25-28 at the Denver Convention Center and Pepsi Center, the 21,000-seat venue where the Denver Nuggets and Colorado Avalanche play.

Dean acknowledged that the change of venue for the convention speech would raise security challenges, but said he and Denver Mayor John Hickenlooper had agreed such challenges won't deter the move.

Ron Perea, Secret Service special agent in charge in Denver, declined to discuss what security precautions the agency would take for the open-air event, including any restrictions on airspace and traffic.

"We're used to this type of thing," he said, citing baseball games where the president throws out the first pitch.

Last month, the convention's host committee reported it was nearly $12 million short of the $40.6 million it had pledged to raise for the effort. Host committee members spoke openly of needing the Obama campaign's help to close the gap.

Dean insisted the convention was operating on budget and the fundraising was proceding apace -- a vew echoed by Obama senior adviser Anita Dunn, who said the campaign was on board to help.

"We're working as a team here," Dunn said. "The fact that the nomination was not decided until the begining of June, clearly many donors would have hung back a little to see if the candidate of their chioice was going to get the nomination."

With a heavy influx of younger voters and Hispanics in recent years, Colorado, once heavily Republican, is one of a handful of states in the mountain West that have been trending more Democratic. Both parties view it as a general-election swing state; Republican John McCain kicked off a five-day economy-focused campaign swing in Denver Monday.

The Obama sought to capitalize on the announcement of the new speech venue in a fundraising e-mail to supporters Monday.

"We're going to kick off the general election with an event that opens up the political process the same way we've opened it up throughout this campaign. Barack has made it clear that this is your convention, not his," campaign manager David Plouffe wrote.

The campaign will choose 10 people who contribute at least $5 to the campaign between now and July 31 to fly to the convention and meet Obama backstage before the speech, Plouffe added.

The Republican National Convention, where John McCain will accept his party's nomination, will be held in Minneapolis-Saint Paul the following week.

FOXNews.com's Greg Salomon and The Associated Press contributed to this report.