If the Jets come out on top against Cablevision in the contentious bidding process for the West Side rail yards, a large portion of the residential development would be rental units, according to some of the real estate developers who are planning to contribute to the $720 million offered by the Jets for the Metropolitan Transportation Authority property.

The developers have offered to pay $440 million for air rights at the site.

The residential real estate market in Manhattan, where the average price of a Manhattan condominium topped $1 million last year, has meant that most recent new developments have been condos, leaving builders of rentals empty-handed.

“It is very hard to build rentals in this strong a market, but this deal will put us in a position that will make it possible,” the president of the Brodsky Organization, Daniel Brodsky, said.

“Buying the air rights would make it financially feasible,” agreed the president of Glenwood Management, Gary Jacobs, who said 80% of his rentals would be market rate, 20% “affordable.”

“This is about business. This area is a good area to develop, but it has been too expensive for rentals,” he said.

Under the Jets proposal, the air rights would be bought at $100 a foot; land at the Hudson Yards neighborhood surrounding the rail yards sells for $150 to $200 a foot.

The Jets proposal, which is contingent on a rezoning, would allow for a Jets stadium on the 13-acre MTA-owned plot, with the remaining acreage transferred outside the rail yards for development. The air rights, which some estimates put at 4.4 million square feet, would likely be transferred to the 59-block Hudson Yards neighborhood, which in January was rezoned to allow for 24 million square feet of additional development.

City Council Speaker Gifford Miller yesterday criticized the Jets proposal, calling it a “double subsidy” and saying that it would take value away from the recently rezoned Hudson Yards.

“This idea that $440 million could be generated through a transfer of air rights immediately is just technically incorrect. There is no mechanism in what we just passed … to make those rights transferable,” Council Member Christine Quinn, who represents the area, said.

The developers, who also include Rockrose Development Corp., which owns at least three sites in the Hudson Yards neighborhood and a number of large rental buildings, see the Jets partnership as a business deal. “We are not part of the Jets bid. This is a business deal,” Mr. Brodsky said.

“After the Jets made their last bid to the MTA, six developers called me expressing a desire to help the Jets, and based on that information, we put together this bid where they could buy the air rights,” the president of the powerful real estate lobby, the Real Estate Board of New York, Steven Spinola, told The New York Sun. “These are developers who care about the West Side – some have sites here and some don’t – and they believe this project will speed up their developments and generate more taxes for the city,” he said.

The developers also include other large-scale developers and managers of rental buildings, including the Related Companies, Jack Resnick & Sons, and Donald Zucker Organization. They did not return repeated calls for comment.

Cablevision refused to comment further on its bid yesterday, issuing a statement proclaiming its bid’s superiority to the Jets’ bid. During a press conference Monday, the company disclosed that its plan calls for 5,800 housing units to be built over the rail yards, along with construction of a public elementary school and a public library. It would not disclose the amount of the bid, which it said is not contingent on a rezoning.

A number of politicians called on the MTA, Cablevision, and the Jets to make the bids public. Rep. Anthony Weiner, a Democrat who represents parts of Queens and Brooklyn, called on the MTA to put the bids on the Internet, to submit them to the city and state comptrollers to be fully audited, and to extend the deadline so that more bids could be submitted. Assembly Member Richard Gottfried also called on the parties to make the documents public.

The think tank the Regional Plan Association issued a statement: “With so much public money at stake, it is crucial that these bids receive a full and open examination to ensure that straphangers are not shortchanged again.”

In other news related to the rail yards, Newmark & Company will remain as advisers to the Metropolitan Transportation Authority regarding the bidding process despite news yesterday that two executives had contributed at least $100,000 to the city’s Olympic campaign.

Buildings owned by the company’s chief executive and vice chairman, Barry Gosin, and chairman, Jeff Gural, donated the money, according to an article published in yesterday’s Newsday.

This is a conflict of interest because a Jets football stadium over the rail yards would double as an Olympic stadium should New York host the 2012 Summer Olympic Games.

“This is serious stuff. This requires a real independent analysis,” Mr. Brodsky said.

The MTA’s board is scheduled to choose from among the three bids by the Jets, Cablevision, and energy company TransGas at a meeting March 31.