The fight for gay marriage reached a significant milestone Friday, when a bill legalizing gay marriage passed through the New York Senate.

New York is now the sixth and largest state in the union to allow homosexuals to marry. The kicker is that New York’s same-sex marriage bill was approved 33-29 by a Republican-controlled state Senate for the first time, indicating an important turning point in not only the battle for marriage equality, but also in party votes.

State legislatures are only just beginning to come to terms with what some courts have known for some time – that discrimination against gays does not stand up to legal or moral scrutiny. In 2000, the Vermont Supreme Court legalized same-sex unions, and Massachusetts followed suit three years later.

But perhaps the most important judicial ruling on the subject came from California’s Republican-dominated Supreme Court in 2008. It declared that discriminating against gays in any way is illegal. In 2009, The Iowa Supreme Court borrowed from California’s decision in another ruling validating same-sex marriage.

It was only later that year that legislators, who unlike judges face re-elections, followed the example of the courts by legalizing gay marriage in New Hampshire and Vermont, two liberal states.

New York has now joined them in the cause with the help of four Republican state senators. This marks a huge turnaround from 2009, when the Democrat-controlled state Senate rejected a similar same-sex marriage bill.

Mark Grisanti, one of the four Republican senators that voted for passage, had even opposed gay marriage in his campaign.

“A man can be wiser today than yesterday, but there can be no respect for that man if he has failed to do his duty,” he said, according to Slate magazine.

In addition, Republican Sen. Stephen Saland said to the Christian Post that he “defined doing the right thing as treating all persons with equality and that equality includes within the definition of marriage.”

“I know my vote is a vote of conscience, and I’m certainly at peace with my vote,” he said.

Their attitudes seem to mark a fundamental change in the nature of the debate over equal rights. It seems that Republicans find it acceptable not only to vote in favor of gay rights, but also to be the deciding votes – without which the bill would have died.

While only six states have legalized gay marriage thus far, New York’s bill may be the catalyst that begins similar efforts around the country in earnest. Such a change is good for the moral fabric of the country.