President Obama is to hold a fundraiser for gay supporters in New York tonight – as the state Senate is expected to vote on a gay marriage bill.

The gala was booked far ahead of the vote, making the timing a coincidence, albeit a happy one for gay rights campaigners.

New York’s legislature is on the brink of legalising gay marriage, with reports claiming that just one more vote is needed to pass the bill.

Mr Obama is to host the event at the Sheraton New York Hotel and Towers, his first fundraiser specifically for LGBT supporters.

Six hundred guests have paid up to $35,800 each to attend the gala and hear the president speak.

The president, who once opposed marriage equality, said in December that his views on the matter were “evolving”.

White House sources have said gay rights campaigners should not expect a presidential endorsement of gay marriage this evening.

However, the president is expected to mention the issue in some way.

Richard Socarides, head of the advocacy group EqualityMatters, told Associated Press: “I do not think that he is going to articulate a new position on Thursday, but I do think that the timing of what we think will be a big win in New York … does up the pressure on him to do something and might just create enough of a political magic moment to bring about a surprise.”

In December, Mr Obama said: “My feelings about this are constantly evolving. I struggle with this.

“My baseline is a strong civil union that provides them the protections and the legal rights that married couples have. And I think that’s the right thing to do.

“But I recognise that from their perspective it is not enough, and I think [it] is something that we’re going to continue to debate, and I personally am going to continue to wrestle with going forward.”