Meghan Keneally Council Speaker Christine Quinn at tonight’s rally.

New York politicos gathered at Cooper Union tonight to kick off the city’s annual Gay Pride celebration, which this year is dominated by the “will they or won’t they” speculation over the State Senate’s impending vote on the Marriage Equality bill.

Though the spectacle’s Broadway-style musical numbers were lighthearted, the real focus was upstate. At last count, 31 senators publicly support the bill, falling just one vote short of the 32 needed to ensure passage. Late Wednesday night, the state assembly passed the bill — and it was the Assembly’s fourth time doing so — leaving the Senate as the final stop before the bill becomes law.

“This is finally our moment,” said Christine C. Quinn, the City Council speaker, who organized the event. “We know this is the moment again that New York can actually call itself the Empire State.”

With the State Senate expected to vote on the bill as soon as tomorrow, activists viewed tonight’s event as a rally for their cause as much as the annual start of the pride celebration.

“We’re hoping it gives us the celebratory momentum that we need,” said Dean Dafis, leader of the New York City chapter of the group Marriage Equality New York.

“I really think it will come to a vote because we have the votes. It’s the first time we’ve got this close,” said Mr. Dafis. “If they don’t vote in favor for it, it will be very hateful against the gay community. People will come out in droves in really almost violent protests.”

Meghan Keneally City Councilwoman Rosie Mendez.

Daniel Hernandez — the 20-year-old intern who rose to national prominence after helping save his boss Rep. Gabrielle Giffords after she was shot in January — and civil rights activist Edie Windsor were honored at the ceremony.

“New York is where the gay equal rights movement started, and its only fitting that it is New York that is the beginning of the end of marriage inequality,” said Mr. Hernandez. “All eyes are on you, New York.”

In her remarks, Ms. Quinn, a potential mayoral candidate, spoke directly to the senators who will vote on the marriage bill.

“You’ll move America to a more perfect union, to a closer place of being the place that our constitution talked about,” Ms. Quinn said of the bill’s passage.

She also had a message for those senators who opposed the bill: “We’re happy to have history pass you by and have you be on the losing side of this battle.”