The Bloomberg administration stood its ground yesterday in defending the stadium project it’s been championing for Manhattan’s far West Side, but critics questioned the mayor’s revenue calculations and his plan to pay off debt.

At a hearing at City Hall, the head of the Independent Budget Office, Ronnie Lowenstein, testified that the project would generate a cumulative $202 million in surplus revenues over 30 years for the city, the state, and the MTA – far less than the $716 million that the Jets, the football team that would play its home games at the proposed New York Sports and Convention Center, predicted.

“We found that over 30 years the stadium will in fact pay for itself, but it will generate far less than the Jets have projected,” the spokesman for the budget office, Doug Turetsky, said. The calculation, which will be included in a report to be released in the next few days, is the first one the fiscal watchdog has done on the stadium’s revenues and costs over a 30-year period.

The findings, which assume the stadium will hold 24 convention or other nonsports events a year, also show that the project will create 3,465 permanent jobs – less than half the administration’s prediction of 7,500.

Deputy Mayor Daniel Doctoroff has been the administration’s primary pitchman for the stadium at the Hudson rail yards site, which is owned by the state controlled Metropolitan Transportation Authority. Testifying yesterday at a City Council hearing, he portrayed the project as both the city’s key asset in securing the 2012 Olympic Games and the centerpiece for the redevelopment of the far West Side. He said it would generate immediate revenue and act as a catalyst for tourism that would pour money into the local economy.

Mr. Doctoroff said he had not seen the IBO numbers but questioned their accuracy.

“I think you have to question the independence of an organization that’s been saying one thing for months and then on the day of the City Council hearing says something different,” Mr. Doctoroff told reporters in City Hall after his testimony.

When asked why he had been using the Independent Budget Office’s past findings to bolster support of the stadium, he said the project was not “embroiled” in controversy at that point so the numbers were more reliable.

Indeed, the deputy mayor used some of the office’s numbers in his presentation to the council’s finance committee an hour earlier, in citing profit projection. He said the city estimates $67 million in profits – above its debt service – the first year the stadium is in use, and $5 billion over 50 years. The IBO, he said, estimates $55 million in revenues in year one and $3.9 billion for the city and state over the next five decades. But the Independent Budget Office disputed the accuracy of some of the numbers Mr. Doctoroff used.

Bloomberg administration officials gave their most detailed explanation yesterday of how they would pay for the $300 million the city has agreed to kick in for the $1.4 billion, 75,000-seat domed facility.

The director of the city’s Office of Management and Budget, Mark Page, said the city would use money from special “Pilot” agreements it has with 261 businesses in the five boroughs to pay down the debt service. Those businesses make payments to the city instead of property taxes.

The payment plan would be funneled through a newly established entity and, according to Mr. Page, would be completely covered by the Pilot revenue. That explanation did not fly with stadium opponents.

The council member who represents the district, Christine Quinn, said it was a “misuse” of the mayor’s authority for a pet project that did not have adequate oversight.

The speaker of the City Council, Gifford Miller, who is hoping to win Mr. Bloomberg’s job in November’s election, made the same argument.

“It appears there seems to be a $71 million slush fund that the mayor can direct in whatever direction he wants,” Mr. Miller said.

“It’s clearly terrible that the mayor is going to take $71 million out of the general fund and direct it where he sees fit without any review of the publicly elected legislature,” he said.

Mr. Doctoroff said tapping the Pilot money was within the mayor’s authority, and he said the sole purpose of the stadium project was to generate money the city could use for initiatives such as education and health care.

Like the Democrats who oppose the stadium, the Independent Budget Office did not see it that way and said the other uses of Pilot funds involved far less money.

“It’s a departure from the way the city has typically operated in the past,” Mr. Turetsky said. “It undercuts transparency and accountability when you are taking city tax revenue.”

Meanwhile, stadium supporters, many of whom filled City Hall chambers yesterday wearing hunter-green shirts with the words “Build It” in white block letters, said the project was the best use of the site and would create thousands of construction jobs. They also pointed out that the project would be on state land and does not require approval from the City Council.

Last Friday, Madison Square Garden offered $600 million for air rights at the site, six times what the Jets proposed paying, and proposed building apartments and a shopping complex there. Mr. Doctoroff predicted yesterday that the offer would probably amount to less than half of that and said that with the recent rezoning of the West Side, more residential development was not needed at the rail yards and would only siphon development from the neighboring areas.

“What we’ve seen out of Cablevision thus far is misleading on its face,” Mr. Doctoroff said, referring to the Garden’s parent company. “Once you subtract the value of the cost of the platform, which they are sticking the MTA with, it is probably down to 250. We assume that they really intend to pay it out over time.”