ALBANY, N.Y. — After weeks of uncertainty and pleas for action by Gov. David Paterson, New York's Senate failed to vote on a bill legalizing same-sex marriage during a special session Tuesday.

Advocates and opponents say the Senate lacked the 32 votes needed to approve the measure, which Paterson strongly supports and the Assembly already passed.

By evening, Paterson put same-sex marriage on agendas for new special sessions for Monday and Tuesday. Later, standing with supporters of the bill, Paterson said he had a commitment by the Senate to bring the issue to a vote by the end of the year, although its outcome remains uncertain. He urged senators who support the measure to ignore "an almost cowardice about battles."

"I implore them that I would rather see an up or down vote, than no action at all," the governor told reporters. "Historically, I think we have lost touch with how movements of equality were reached. There were a lot of ups and downs," he said, citing the civil rights movement as an example.

"If this bill is put on the floor, there are a lot of people whose consciences will let them vote for the bill, but who just don't want to stomach all the activity around them if they take a position before the vote," he added.

The Rev. Jason McGuire of New Yorkers for Constitutional Freedoms, which opposes same-sex marriage, called it a "crushing blow" to same-sex marriage advocates.

"I'm a little hesitant to call it dead yet," McGuire said. "It's never over until it's over ... but if they had the votes it would have gone to the floor."

McGuire acknowledged the issue could re-emerge before Jan. 1, but said he doubted lawmakers would be inclined to consider it next year, when they all face re-election.

McGuire said last week's special election for New York's rural 23rd Congressional District showed a resurgence in the power of the Conservative Party, which opposes gay marriage, and "marginal" incumbents won't want to risk their seats for the issue.

In the congressional race, Conservative candidate Doug Hoffman forced the more moderate Republican nominee, Dierdre Scozzafava, to suspend her campaign by passing her in the polls and in fundraising. Hoffman narrowly lost the race to Democrat Bill Owens.

The bill's sponsor, Sen. Thomas Duane of Manhattan, refused to comment even on whether he wants it to get to the floor, where approval is uncertain.

When asked if he feels the bill will eventually be approved, he said: "I'm very optimistic."

The Senate convened and adjourned after less than 30 minutes, the vast majority of which was spent honoring members who were military veterans. Same-sex marriage wasn't debated or on the agenda.

Paterson has said he would sign the measure into law and pressed senators to follow the lead of the Assembly, which passed it earlier this year. Legislators said Tuesday they may return next week as well as in December.

The leading opponent of the measure in the Senate, Sen. Ruben Diaz Sr., a Bronx Democrat and conservative minister, said he was prepared to strongly oppose the bill and the governor, who promised its passage this year. Diaz said he canceled a cruise with his wife this week — Tuesday is her birthday — and lost a deposit "because of this governor."

The measure wasn't brought to the floor after the Assembly acted in the spring because there weren't enough votes in the 32-30 Democratic majority to pass it. A few Democrats opposed the bill on religious grounds.

It's likely some Republican votes will be needed for passage. Republican leader Dean Skelos of Nassau County has released his members to act as they see fit, freeing them from the usual practice of bloc voting.