COPENHAGEN, (Reuters) – The frantic, last-minute  lobbying by the four rival cities bidding for the 2016 Summer  Olympics closed yesterday with a shift of pace as IOC members  forgot the polemics and relaxed with a gentle evening of ballet.

Copenhagen’s ultra-modern Opera House staged the opening  ceremony of the IOC session which will today determine  whether Chicago, Madrid, Rio de Janeiro or Tokyo will win the  right to host 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.

U.S. President Barack Obama was due to fly in to the Danish capital early today 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.

But the other three candidate cities were all 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 on  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 yesterday to join the Tokyo delegation at  Friday’s presentation.

CHICAGO FAVOURITES

London bookmakers make Chicago the favourite with Rio its  closest adversary and Tokyo and Madrid a little further behind.

President Obama’s visit is seen by many as a high-risk  strategy which could result in negative political fallout should  Chicago fail to win the vote.

A Seton Hall Sports Poll of more than 1,000 Americans across  the country, published in the U.S. yesterday, showed 60  percent thought Obama’s prestige could be affected by the result  and only 10 percent thought his trip to Denmark would guarantee  success. 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 organisation, 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.    Today’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. Chicago go first, followed by  Tokyo, Rio and Madrid.

The vote begins at 1510 GMT and Rogge will announce the  winner in a globally televised ceremony starting at 1630 GMT.