SAN DIEGO — San Francisco mayor Gavin Newsom envisions a 2016 Summer Olympics with marathoners crossing the Golden Gate Bridge, cyclists pedaling through the Presidio and sailors navigating his city's scenic bay.

If sprawling Los Angeles is given a chance to host its third Olympics, Mayor Antonio Villaraigosa thinks the games would be more compact and easier to get to than in 1984, and in several venues built since those successful games.

Mayor Richard M. Daley promises games presented "Chicago style."

Houston has big-hitting businessmen and some big venues on its side, and Philadelphia has history.

That's what the U.S. Olympic Committee board of directors has to chose from, if it decides to bid on the 2016 Games.

"There was nobody that eliminated themselves, based on the information we have now," said USOC chairman Peter Ueberroth, the architect of the 1984 Los Angeles Games, which were the first to turn a profit.

"We think that we'll bid, we hope we'll bid, we want to bid, but we may not if we don't think it's a fair chance," Ueberroth said. "We're not going to take a partner, whatever city is chosen, and take that partner on a fool's voyage."

The USOC has set a deadline of the end of the year to decide whether to bid for 2016. If it does, it will pick a city by the end of March. The International Olympic Committee will pick a city in 2009.

Ueberroth also said the USOC is facing "major, major obstacles" in illegal drug use, such as HGH, and revenue from television and sponsors.

The USOC hasn't begun negotiating TV deals for 2016.

Stephanie Naidoff, commerce director for the City of Brotherly Love, said she had "every confidence that Philadelphia can deliver on the Olympic dream that not only will make the U.S. Olympic Committee proud, but will make all of America proud."

Asked about venues, she said: "We believe we have most of what we need."