Nassau County District Attorney Kathleen Rice said yesterday that she plans to sue the federal government over the Defense of Marriage Act if she becomes New York’s next attorney general.

“It’s time attorneys general around the country begin to challenge the legality of this discriminatory law,” Rice said. “I will be proud to be among the first AG’s to challenge DOMA and to tell the federal government that New Yorkers refuse to be subjected to government-mandated discrimination.”

The lawsuit would allege that by defining marriage between a man and a woman, DOMA infringes on state’s rights to define and regulate marriage as they see fit. Although same-sex marriage is not legal here, New York does recognize gay marriages performed in other states.

The suit would follow on the heels of a similar one by Massachusetts attorney general Martha Coakley filed in 2009 and the Ted Olson and David Boies lawsuit currently making its way through the 9^th Circuit Court of Appeals in California.

The Massachusetts suit says that DOMA denies same-sex couples the right to federal benefits like social security and Medicaid even though those couples are legally married by the state.

Because the suit would be filed after the others, it is unlikely to make it to the Supreme Court unless it gets merged with the Massachusetts or California cases, legal experts said.

But the effort still could have resonance.

“There is certainly an argument to be made on how lawsuits are just as important for the public education benefits that they provide about injustices and inequalities,” said Fred Sainz, a spokesman for the Human Rights Campaign. “Past AG’s from the great state of New York have been able to command quite a bit of attention with their lawsuits.”

And, in a campaign season, the move has political implications as well.

Rice is currently one of five Democrats vying to become the state’s top law enforcement official, and her opponents have been trying to paint her as the moderate in the field.

With this announcement however, Rice shows that she is making a major play for LGBT voters. She is first attorney general to call for the suing of the federal government over DOMA. And tonight her campaign will hold an LGBT fundraiser hosted by Michelle Clunie, the star of Bravo’s “Queer as Folk,” and a former girlfriend of state Senator Eric Schneiderman, one of Rice’s chief rivals for the nomination.

Schneiderman will be holding his own LGBT fundraiser tonight, hosted by city council speaker Christine Quinn.

A marriage equality vote failed in the state Senate last year, and LGBT voters are gearing up for an active role this election season.

“There is a great deal of frustration in New York, obviously,” Sainz said. “With the lack of progress on marriage.”