Sources say New York Governor David Paterson introduced a gay marriage law that would make the state the fifth, and the highest profile, allowing same-sex couples to wed.
"I'm introducing a bill to bring marriage equality to the state of New York," Paterson said in an announcement carried live on NY1 television.
"We have an honor and a duty to make sure that equality exists for everyone," he said, comparing the issue to racial, sexist, and religious rights.
"We have all known the wrath of discrimination.... We stand to tell the world that we want equality for everyone. We stand to tell the world that we want marriage equality."
However it remained far from certain that the law would overcome significant opposition in the assembly in the state capital Albany. The same bill was rejected in 2007.
The initiative comes on the heels of similar laws being passed in Vermont last week, and previously in Connecticut, Iowa and Massachusetts.
California, meanwhile, remains locked in a bitter legal battle between pro- and anti-gay marriage camps.
The Supreme Court in San Francisco legalized gay marriage in a landmark ruling last May, but in November voters passed a change to California's constitution that redefined marriage as a union between a man and woman.
In 2007, the gay marriage bill passed in New York's lower house, but failed in the then-Republican led upper chamber. Democrats now have a slim majority in the upper house, but observers say that may not be enough.