Gridiron fans, move over.

The Barack Obama campaign hopes to turn the last evening of the Democratic National Convention in Denver on Aug. 28 into a giant rally of voters in a football stadium.

The unusual move, confirmed by two sources, would be an echo of John F. Kennedy’s acceptance speech in 1960. Kennedy delivered his address before thousands of supporters at the Los Angeles Memorial Coliseum. Obama’s big moment also would fall on the 45th anniversary of Dr. Martin Luther King Jr.’s “I Have a Dream” speech, delivered at the Lincoln Memorial in Washington.

The first three days of this year’s convention are still scheduled to be held at downtown Denver’s Pepsi Center, a basketball and hockey arena. But the Pepsi Center holds no more than about 19,000 people, and the Obama campaign thinks it can assemble a much bigger crowd for the acceptance speech — making a more compelling television picture.

Invesco Field, home of the Denver Broncos pro football team, can seat more than 76,000.

Officials involved in planning the event said the challenge of filling the stadium didn’t seem to be much of a worry for the Obamians, who attracted huge crowds during their primary campaign this spring. More worrisome, they said, were issues of logistics and security for all the Democratic dignitaries at the convention — plus the possibility of afternoon thunderstorms in the open-air stadium.

The football stadium plan appears to be what was in the works when word surfaced earlier this week that the Obama campaign and the Democratic National Committee were kicking around the idea of shortening the party convention to three days instead of four.

Obama campaign officials didn’t respond to requests for confirmation. Shannon Gilson, a spokeswoman for the campaign, simply told the Denver Post via e-mail: “We think Thursday night in Denver will be very special.”

-- Doyle McManus