Lobbying for 2016 Games closes COPENHAGEN – In 30 minutes, it will be over. Years of preparations, arm-twisting, sweet-talking and hopes will be rejected or rewarded Friday when the International Olympic Committee votes to select the host for the 2016 Games. Chicago, Rio de Janeiro, Madrid and Tokyo - one by one - will be eliminated in a tense half-hour of successive rounds of secret balloting until one stands alone. Shortly afterward, IOC President Jacques Rogge will break open a sealed envelope containing the winner's name and utter the magic words: “The games of the 31st Olympiad are awarded to the city of ...” But on the eve of the vote, the IOC's 106 members were, as ever, keeping their thoughts to themselves. Only Tokyo seemed to have fallen out of the running. Otherwise, it was still too close to call between the beaches and bossa nova of Rio, the bustle and Lake Michigan waterfront of Chicago or the European elegance of Madrid. Everyone had reason to be hopeful, none reason to be sure. The frantic, last-minute lobbying by the four rival cities bidding for the Olympics closed Thursday with a shift of pace as IOC members tried to relax with a gentle evening of ballet. Copenhagen's Opera House staged the opening ceremony of the IOC session which will Friday determine the host of the 2016 Games. Denmark's royal family, headed by Queen Margrethe and Crown Prince Frederik, greeted the visiting dignitaries at the glistening glass building, including some illustrious rivals, King Juan Carlos of Spain and American First Lady Michelle Obama, backing Madrid and Chicago respectively. US President Barack Obama was due to fly in to the Danish capital early Friday to join his wife and address the session as part of the Windy City's team. The First Lady spent her day in a series of high-level meetings and one-on-one encounters with IOC members in what the Chicago delegation hopes could be a decisive factor in swinging the vote. The other three candidate cities were strenuously lobbying in the Danish capital too. Brazilian President Luis Inacio Lula Da Silva even borrowed Obama's election mantra “Yes, we can” in a news conference Thursday in support of the Rio bid. Spanish Prime Minister Jose Luis Zapatero pointed to major Spanish successes at soccer, basketball, cycling and tennis as a reason to support Madrid at his news conference. Tokyo's newly elected Prime Minister Yukio Hatoyama was flying in late Thursday to join the Tokyo delegation at Friday's presentation. IOC President Jacques Rogge carefully avoided mention of the candidates in his speech at the opening ceremony. He told his audience that the IOC had weathered the negative effects of recession well and was in good economic shape for the future. “Like every other major organization, we have felt the effects of the global economic downturn,” Rogge, president since 2001, said. “We have met the challenges together, and our movement is as strong as ever.” He said the IOC would continue its zero-tolerance policies on doping in sport, match-fixing and corruption. Friday's first day of the IOC session will be devoted entirely to choosing the 2016 Games venue. Each of the four cities will make a 45-minute presentation of videos and speeches, followed by a 15-minute question-and-answer session. The vote begins at 1510 GMT and Rogge will announce the winner in a globally televised ceremony starting at 1630 GMT.