Here is a CNN commentary by Olympic gold medalist Sarah Hughes regarding Chicago's bid for the 2016 Olympics where she doesn't actually comment on much aside from...the Olympics are good and the bid is for unity, because that's what Obama said in a letter. She doesn't even explicitly state that she supports Chicago's bid. She just says the Obamas are going to Copenhagen (actually, she says Michelle Obama is already there) and trying to push for the Olympics - the first time an American president is attending the host city vote.
Oddly enough, when I lived in New York and it was lobbying for the games a few years ago, I was very much opposed to the bid, for many reasons. But I've also lived in Chicago and I think it would be a fabulous host for the games. Different cities, capabilities, and motivations, I guess. Anyway, good luck Chicago!