New York Senator Mark Grisanti is the main target in a new anti-gay marriage campaign by the National Organization for Marriage (NOM).

Grisanti is among the four GOP senators who crossed the aisle to vote with all but one Democrat, Senator Ruben Diaz Sr. of the Bronx, to approve a gay marriage bill last month in the Empire State. The law takes effect on Sunday, July 24.

Another three Democrats previously opposed to marriage equality also switched their votes.

However, Grisanti, who is considered the most vulnerable of the four Republicans, has become the main target in a new campaign from the nation's most vociferous opponent of gay marriage.

NOM has already pledged $2 million to boot out the seven senators.

In a new flier, the group says Grisanti, like Benedict Arnold, sold out his country to the highest bidder.

“Senator Mark Grisanti sold out our shared principles in a betrayal reminiscent of Benedict Arnold's plot to surrender West Point to the British,” the ad states.

Another flier reads: “Let Mark Grisanti know you won't forget his betrayal.”

NOM is also organizing rallies protesting the law in four cities – Manhattan, Rochester, Albany and Buffalo – to coincide with the law's start on Sunday.