LENOX HILL — A powerfulUpper East Side Democratic organization was poised to endorse Christine Quinn for mayor, but shifted course because of the City Council speaker’s stance on thecontroversial marine transfer station, an organization leader said.

The Lenox Hill Democratic Club, which endorses candidates each election cycle and then petitions to put these picks on the ballot, isn’t just turned off to Quinn. They have decided to pass on endorsing any mayoral hopeful because the Democratic front runners largely back the East 91st Street Marine Transfer Station, club president David Menegon said.

“The club has voted and it is finalized,” he said. “This is a done deal.”

Menegon said that the club’s approximately 100 members generally had favorable feeling towards Quinn in particular and would have been inclined to support her — but not enough to get past her advocacy of one of the most polarizing public works project on the Upper East Side.

“There are a lot of people that are very positive towards Christine Quinn, but her position on the waste transfer station basically eliminated us from endorsing her,” he said.

“That’s sending a clear message: We’re not putting her on the ballot.”

Though Lenox Hill does not fall within Yorkville — the area most impacted by the East 91st Street Marine Transfer Station — Menegon said the issue impacts the entire neighborhood.

Opponents of the East 91st Street transfer station have long claimed that it will wreak havoc on the quality of life on residential streets of the East 70s, 80s and 90s — both by bringing vermin, noise, as well as a host of health and traffic-safety concerns.

“What happens on the East Side of the street still affects other people in the neighborhood,” Menegon said.

This is not the first time that the East 91st Street Project — long part of the city’s comprehensive waste management plan under Mayor Michael Bloomberg — has presented the potential to being politically damaging to Quinn.

At a rally last week, anti-MTS activist group Pledge 2 Protect vowed to keep project supporters out of office — and had the backing of influential neighborhood politicians.

“You’re not getting votes in this community,” said Assemblyman Micah Kellner, referring to the mayoral hopefuls and other candidates. “This neighborhood can swing this election.”

Menegon also said that further developments in the mayoral race — such as Quinn’srecent discussion of her battle with alcoholism and bulimia — would not impact the club’s decision.

“It’s not like we watch the news everyday after we make a decision, and then reconvene the whole club to make choices or change what we’ve done,” he said.

A spokesperson for Quinn declined to comment.

The club would not further discuss candidate Sal Albanese‘s recent decision to oppose the East 91st Street project, either, Menegon added.

A spokesman for Albanese said the former city councilman didn’t make his decision for political favors.

“Sal did not do this to get an endorsement,” the campaign spokesman told DNAinfo New York. “He took a stand because it’s the right thing to do.

“We think that’s what candidates for mayor should do,” the spokesman added. “They should have the political courage to do the right thing whether it brings them a political endorsement or not. We think it’s unfortunate that nobody else has taken a stance.”

Other Democrat mayoral candidates passed up by the club — such as Comptroller John Liu, former comptroller and runner-up in the last mayoral election Bill Thompson, and Public Advocate Bill de Blasio — did not respond to requests for comment.

Read the story on DNAinfo.