FILE PHOTO - A spectator wears a shirt with the word 'LOVE' on it while watching the San Francisco gay pride parade, California
FILE PHOTO - A spectator wears a shirt with the word 'LOVE' on it while watching the San Francisco gay pride parade two days after the U.S. Supreme Court's landmark decision that legalized same-sex marriage throughout the country in San Francisco, California June 28, 2015. Reuters

A bipartisan group of U.S. senators on Thursday decided to put off until after the Nov. 8 congressional elections any vote on legislation protecting gay marriage, dashing the hopes of advocates who sought prompt action on a bill already passed by the House of Representatives.

The move came after weeks of closed-door talks between a small group of Democratic and Republican senators who looked at ways to amend the House bill in order to attract at least 10 Republican supporters who would join 48 Democrats and two independents.

The U.S. Census Bureau in 2019 estimated that there were 543,000 same-sex married couple households and 469,000 households with same-sex unmarried partners living together.

A formal statement on the delay was expected later on Thursday, but Democratic Senator Tammy Baldwin informed reporters of the delay.

"We're very confident that the bill will pass but we will need a little more time," Baldwin said, adding that a bill will be put to a vote after the elections.

The gamble is that following the midterm elections Republican senators will feel freer to back the legislation at a time when voter backlash would be two years away with the next elections.

"If they think that improves their chances of passage, that's their prerogative," Republican Senator John Cornyn told reporters, adding that he would vote against a bill codifying same-sex marriage into law.

Failure to win enough Republican support in the Senate for a bill that passed the House in mid-July with the backing of 47 Republicans was a disappointment to Senate Majority Leader Chuck Schumer, who had hoped to set up a first procedural vote on the legislation on Monday.

At the same time, Schumer has been careful to give negotiators -- and wavering Republicans -- the space they needed to put together a bill that would succeed, rather than just force senators to go on record for or against but result in a failed vote.

Over the past several days, the small group of senators and their staffs worked on an amendment designed to protect the "religious liberty" concerns of some Republicans.

But some supporters of the bill said the real snag was that there just were not enough Republicans willing to back any such bill, especially six weeks before the elections.

"The Republicans need to stand up and explain why they don't want to vote for equality among all human beings and the right to marry the person you love," Democratic Senator Elizabeth Warren told reporters upon hearing about the delay.

But Republican Senator Rob Portman said that with Schumer needing a decision on Thursday so that he could arrange for a first vote on Monday, Republican holdouts needed more time to review the amendment to the bill that was being negotiated before they could become a "yes" vote.

"We were very, very close," Portman said.

The push to enact a federal law recognizing gay marriage arose after conservative U.S. Supreme Court Justice Clarence Thomas in June wrote that the same logic that led the court to overturn the national right to abortion could also lead it to reconsider its earlier decision legalizing same-sex marriage.

Early on, Senator Mitt Romney was one of several Republicans saying there was no need to tackle such legislation after the Supreme Court ruled in 2015 that the right to marry is guaranteed to same-sex couples.

The court in 2015, however, was markedly less conservative than the current high court.

Supporters of the legislation fear that the delay - the second in two months - could see support further erode, especially if Republicans win in November elections.