Christine Quinn, Real Estate Insider

“She’s always been open to listening to development projects,” said Mr. Durst. “She hadn’t been simply against [the West Side stadium] because she’s against development. She’s been against bad development.”

Ms. Quinn did not respond to a request for an interview by deadline, but it is far from clear that the request for proposals that she helped negotiate was friendly to developers. Many community leaders said that Ms. Quinn got as much as could be expected on the two hot issues: affordable housing and preserving the High Line, the elevated rail line (and future park) whose northern portion winds around the rail yards.

“I wish there were stronger requirements for affordable housing, but fundamentally we appreciate it will go through ULURP, and we think there is some room to negotiate improvement during the land-review process,” said John Raskin, organizing director for Housing Conservation Coordinators, a West Side not-for-profit. “The site needs to be developed. It is not incredibly useful sitting as an empty rail yard.”

Neither the preservation of the High Line nor the affordable housing is, however, guaranteed, which makes it hard to determine whether the development will both provide the “give-backs” Ms. Quinn spoke about and be attractive enough that developers will want to pay a high price for it—thereby providing much-needed capital funds to the M.T.A.

The real test is what happens over the next three months, as developers put their bids together and shape the future of the West Side—and of Ms. Quinn’s political career.