Ninety-nine of the IOC's 106 members are eligible to vote in the first round (members from countries with bid cities can't vote while their candidate is still in contention).The last sentence is interesting and is something we just read for the first time. We think they're implying that Asian countries have less animosity towards the United States then European ones, but who knows.
The city receiving the fewest votes is eliminated after each round until one candidate secures a majority. The vote is expected to go the maximum three rounds.
Some members tend to vote out of sympathy in the first round, which can produce some surprises. The key to victory is picking up votes from the cities which go out.
If Tokyo were to go out in the first round, it is believed many of its votes would go to Chicago. If Madrid goes out, the consensus is they would go to Rio.
Anyway, it's safe to say that experts are predicting that the race is between Rio and Chicago. At this point, if you don't know the criticisms of Chicago's bid, you must be living under a rock. However, we don't hear as much about Rio's negatives. Time magazine's website has an interesting article on the empty promises of Rio's 'successful' 2007 Pan American games:
Winning the 2007 Pan American games was considered a big, if sometimes chaotic, success for Rio. To triumph over rival bidder San Antonio, officials used the same argument that this was Rio's turn. To back that up they promised to transform the city with a new ring road system, something called a "via light" railway (presumably a light railway), a new state highway and 54 km of new metro line.If you think Rio has it in the bag, read the article. Neither city is perfect...we're looking forward to the coverage next week.
But none of the roads and not one kilometer of proposed metro lines was built. Authorities also promised to clean up the Guanabara Bay, the fetid body of water whose smell assails visitors driving into town from the international airport. Although hundreds of millions of dollars have been spent, the stench persists and the bay remains a stinking eyesore.
(Olympic image from 121st IOC Session & XII Olympic Congress in Copenhagen website)