President Obama will put his international star power on the line this week as he travels to Denmark for a last-minute, in-person appeal to members of the International Olympic Committee to choose his hometown of Chicago to host the 2016 Summer Games.
The president had initially said he would have to skip the final presentation to the IOC, which will occur just prior to the committee's selection from among four finalists, Chicago, Tokyo, Madrid and Rio de Janeiro. But in a bit of theatrics, Mr. Obama reversed course and announced Monday he would attend.
Mr. Obama has made no secret of his desire to capture the games for Chicago.
"Chicago is ready. The American people are ready. We want these games. We want them," he said during a speech at the White House earlier this month.
For a vote that is expected to hinge on the leanings of just a handful of IOC members, his visit could be pivotal.
"I think his presence makes it almost certain that Chicago will win the bid," said former Massachusetts Republican Gov. Mitt Romney, who oversaw the Salt Lake City Winter Olympics in 2002. "I think we could have easily lost the bid" had the president not gone to make the case for Chicago in person.
But there is also a political risk that Mr. Obama's personal intervention falls short, dealing the new president a very public defeat on a global stage.
The presidential pitch is part of a well-orchestrated lobbying campaign involving the White House. In June, Mr. Obama created the White House Office of Olympic, Paralympic and Youth Sport. Last week, he raised the topic repeatedly with world leaders as they gathered at the United Nations and at the G-20 meeting in Pittsburgh.
Observers of the bid process said Mr. Obama's presence this week will help, especially considering that the heads of state of Brazil and Spain and Japan's prime minister are all expected to attend.
IOC delegates have come to expect a personal appeal from the very top from its bidders.
In the weeks leading up to the vote for the 2012 Summer Olympic Games, London's chances of winning seemed remote, with many observers predicting the IOC would award the games to Paris.
But London surged to win the bid on the final day after British Prime Minister Tony Blair arrived before the final vote in Singapore to speak with IOC members. Like Mr. Obama, Mr. Blair had originally said he could not attend the IOC gathering.
Russia's Sochi bid for the 2014 Winter Olympic Games, once seen as a long shot, also got an unexpected boost when then-President Vladimir Putin spoke during the bid presentation on the final day, one of the few occasions he has spoken publicly in English.
Mr. Obama's decision to attend "is absolutely huge," said Terry Lyons, a New York-based sports marketing consultant who has worked with many Olympic teams and athletes. "He has a real understanding and true knowledge of everything that's gone on there and backing up the bid. I also think it's a statement of his belief in sport as a very important part of society, and I think that will carry a lot of weight with the IOC."
Chicago's organizers will make their final presentation to IOC officials on Friday morning, with the other bidding cities to follow. IOC members will then vote in as many as three rounds, eliminating the lowest-scoring city each round. The first city to capture at least 50 percent of the vote will win.
Past votes suggest the contest will go down to the wire. London and Sochi each won in the final round of voting by a mere four votes. Sydney, Australia, was awarded the rights to the 2000 Summer Olympics by two votes in the final tally, despite badly trailing front-runner Beijing in the first three rounds.
"Obama will matter a lot, definitely, especially since it's so close," said Rob Livingstone, the producer of Gamesbids.com, a Web site devoted to the Olympic bid process. "Any edge you can get is very important."
Predicting an IOC decision is inherently challenging, and recent technical evaluations of the bids offered few clues on the committee's leanings. The IOC had been critical of Chicago's inability to get a full financial guarantee from the federal government to protect against cost overruns, but those concerns were addressed earlier this month when the Chicago City Council passed a measure ensuring a full financial guarantee at the local level.
All four cities have mounted strong public relations campaigns touting the technical side of their bids, but Olympic observers said emotional arguments often play a bigger role. Some give the edge in Copenhagen to Rio de Janeiro because IOC members might be moved by the notion of holding an Olympics in South America for the first time. Brazil has also played up its high level of support from its citizens.
But analysts said Mr. Obama's presence will boost Chicago's profile.
"What Chicago can use to their advantage is to say that President Obama calls Chicago his hometown and they could try to, in the presentation, use the emotion and swing the votes their way," Mr. Livingstone said. "The final presentation is going to be very, very important to the final results of this election."