This is a great article on how the debate and political process evolved from failed efforts in 2009. It focuses on not only legislators' personal struggles, but the new governor's tact, using wealthy Republican donors, encouraging business to get on board, and limiting the influence of the Catholic Church. It's worth a few minutes to read the entire thing.
"The story of how same-sex marriage became legal in New York is about shifting public sentiment and individual lawmakers moved by emotional appeals from gay couples who wish to be wed.
"But, behind the scenes, it was really about a Republican Party reckoning with a profoundly changing power dynamic, where Wall Street donors and gay-rights advocates demonstrated more might and muscle than a Roman Catholic hierarchy and an ineffective opposition.
"And it was about a Democratic governor, himself a Catholic, who used the force of his personality and relentlessly strategic mind to persuade conflicted lawmakers to take a historic leap."