This report from The Capitol suggests that NY republicans understand where their constituents are on the question of marriage:
In private conversations around the Capitol, top Democratic lawmakers expressed serious misgivings about the likelihood that any bill would pass this session. At a certain point, they said, political reality takes over: The Senate is controlled by Republicans, and so far not a single Republican senator is willing yet to stand with Bloomberg and Quinn for gay marriage.
... Senate Republicans have little to gain politically from voting “Yes” on gay marriage, the numbers suggest. Even if the governor is willing to cut a deal behind closed doors to bring the issue to the floor, some Republican senators who vote for gay marriage would still face a very real threat to their seats.