Friday October 2 is D Day for the four cities vying to host the 2016 Summer Olympic Games.

And in not wanting to be outdone in the heads of state stakes, an impressive list of world leaders has been announced in the run-up to Friday’s vote with the latest addition being US President Barack Obama. President Obama will be accompanied by wife Michelle, originally announced as Chicago’s main drawcard.

Also confirmed are Japan’s brand new Prime Minister Yukio Hatoyama, Brazil’s President Lula, more formally known as Luiz Inácio Lula da Silva, and King Juan Carlos of Spain.

The presence of such high profile leaders, including United Nations Secretary-General Ban Ki-moon will no doubt put pressure on the Danish Security and Intelligence Service, known as Politiets Efterretningstjeneste or PET for short.

On Friday in Copenhagen’s Bella Centre each city will get exactly 70 minutes to present their case to the IOC with Chicago first cab off the rank, followed by Tokyo, Rio de Janeiro and Madrid.

Chicago’s bid carries the United States hopes after the loss of New York to London in the campaign to hold the 2014 Games. The United States has hosted four Summer Olympic Games, more than any other nation.

Japan has already hosted a Summer Games in Tokyo in 1964 and Winter Games in Sapporo (1972) and Nagano (1998).

Rio de Janeiro rests its chances on the fact that a Games has never been awarded to South America, and Madrid hopes to emulate Barcelona’s success in securing the 1992 Summer Olympics.