"You can play a great game and still not win," Obama said at the White House, shortly after returning from Copenhagen where his in-person plea did not put Chicago over the top. "Although I wish that we had come back with better news from Copenhagen, I could not be prouder."
Obama expressed no regret at putting so much on the line for the failed effort.
"I have no doubt that it was the strongest bid possible and I'm proud that I was able to come in and help make that case in person," the president said.
His chief spokesman, Robert Gibbs, told reporters that Obama got the bad news aboard Air Force One as he and his wife, Michelle, flew back to Washington from the Danish capital. He was watching TV alone in his quarters on the presidential jet.
Michelle Obama had gone to Copenhagen before her husband and had lobbied hard for the Summer Games to be brought to her hometown and his adopted hometown.
Chicago's early exit from finalist balloting represented a personal setback for Obama and a painful defeat for Chicago, America's most prominent Midwestern city.
The president put his personal prestige and political capital at risk when he decided late in the competition to go to Copenhagen and make a personal appeal.
"Absolutely," Gibbs replied, when asked whether Obama was glad he'd made such a large commitment to lobbying for the Games.
He said the president "would never shy away from traveling anywhere, talking to anyone about this country."
Many people had assumed Chicago would be a finalist. But International Olympic Committee members eliminated it only hours after Obama and his wife urged them to send the Summer Games there. With Madrid and Tokyo also in the running, Rio de Janeiro won the intense competition.
Obama praised that decision as a "truly historic event" and said he called Brazilian President Luiz Inacio Lula da Silva from his plane to offer congratulations -- tinged with a friendly taunt on 2016. "Our athletes will see him on the field of competition," Obama said.
In making his pitch, the president had said that a nation shaped by the people of the world "wants a chance to inspire it once more."
Never before had a U.S. president made such an in-person appeal, and Obama's critics will doubtlessly see the vote as a sign of his political shortcomings.
The president's whirlwind trip put him in the Danish capital for less than five hours Friday, with Chicago-backers hoping that would be sufficient to give the city the advantage it needed to win the close, four-way race to become the host city.