Sen. James Alesi, a Republican no vote in 2009, said he plans to vote yes on same-sex marriage, the first GOP lawmaker to move to the affirmative column.

Meanwhile, an administration official says Gov. Andrew Cuomo plans to introduce his same-sex marriage bill “soon” with a copy of the text available later tonight. The introduction of the bill is a clear sign that the governor believes a vote in the Republican-led Senate would be successfully.

Two more votes are needed in order for the measure to be approved in the Senate, which needs a 32-vote majority. Two more Republicans would have to become yes votes in order to do so.

Alesi, addressing the media after a meeting with Cuomo in his office, said he was “wrong” to vote no in 2009 and that he apologized for casting a “political vote.”

Alesi had long suggested he was drifting toward voting yes this time around, referring openly to “marriage eqality” — the buzz phrase used by pro-same-sex marriage advocates.

His new stance also comes as after three Senate Democrats — Shirley Huntley, Joe Addabbo and Carl Kruger — said they would vote yes. All voted no in 2009.

Now attention will likely turn to the other undecided Republicans, Sens. Greg Ball, Andrew Lanza, Steve Saland and Roy McDonald.

While at least two would have to vote yes, it’s possible that all four would be needed in order to provide political “cover” and avoid being the deciding 32nd vote.