On a day when a proposal for a stadium on the West Side of Manhattan suffered what seemed a fatal blow, the International Olympic Committee published a report yesterday that gave a positive picture of New York as a potential host city for the 2012 Olympics.

The report by the evaluation commission led some outside students of the Olympic selection process to conclude that even with the rebuff to the Jets stadium, which was to be the main Olympic venue, it is possible that when the 115 IOC members meet in Singapore on July 6 to vote on a host city, they may still choose New York.

“It is highly unlikely, but it is possible they could still choose New York,” Gamebids.org’s Robert Livingstone, who writes a weekly column on the 2012 Games for The New York Sun, said. There is also a chance, however, that New York could be removed from the ballot because it no longer has the prospect of a key venue that was part of its bid.

While noting New York’s inability to guarantee “the Olympic Square site,” which was to include the stadium and the International Broadcast Center, the evaluation commission touted New York as a 2012 site.

In characteristically measured language, the evaluators praised the “very strong tradition of sponsorship and licensing in the New York and USA markets”; they decided New York’s “average temperatures … and humidity levels at proposed Games-time are satisfactory,” and they said a New York Olympics would “leave … positive environmental and sustainable development legacies for the city.”

“We are in the top tier of cities, and if the stadium is approved, we have an excellent chance of winning,” Deputy Mayor Daniel Doctoroff, who founded the Olympic bid group NYC2012, said yesterday morning before the Public Authorities Control Board withheld approval of the Jets stadium.

In a statement, NYC2012 called the decision by the Assembly speaker, Sheldon Silver, and the Senate majority leader, Joseph Bruno, to abstain from voting “inexplicable and terribly damaging to New York’s and America’s Olympic bid.”

“Rejection of the stadium will seriously damage our chances at winning the 2012 games,” Mayor Bloomberg said yesterday, shortly before the Albany politicians met to vote on the plan.

Mr. Bloomberg said he would be talking to the United States Olympic Committee in the coming days, “but as today’s reports from the IOC showed, we would be very unlikely to be selected without an Olympic stadium guaranteed.” The mayor also said Olympic rules do not allow a bid city to change its proposal, eliminating the possibility that the Olympic stadium could be built instead at Willets Point in Queens, which has been discussed as a backup site should the Jets plan fail.

The reports do not rank the bid cities, but Paris and London were generally considered the front-runners both before and after the document was published. The report had scarce criticism of the Paris bid, and the only soft spot in London’s bid may be its ambitious plan to spend more than $30 billion in the next seven years to improve its transportation infrastructure.

Madrid’s Olympic Village was its weak spot, needing “some revision to the design and layout … to ensure conformity with the IOC requirements,” the report said.

The evaluation of Moscow included several criticisms, and experts generally characterized the Russian city as not a major contender.