Prosecutors will take a fresh look at the 1992 death of gay icon and “mayor of Christopher Street” Marsha P. Johnson, the Daily News has learned. Johnson, an unmistakable Greenwich Village fixture who posed for an Andy Warhol series on drag queens, was pulled from the Hudson River, fully clothed, near Christopher St. on July 6, 1992. She had been missing for days. Her death was ruled a suicide by the city’s medical examiner, but Johnson’s friends and family believe she was attacked by bullies who regularly harassed and assaulted her at the pier. The ruling was changed from “suicide” to “undetermined” in December 2002, as a result of a police investigation that determined there was not enough information to call it a suicide. Now, two decades after her death, the Manhattan District Attorney’s office has agreed to reconsider the case, law enforcement sources confirmed. “We think it’s important that this case is closed with the accuracy of science and modern technology,” said transgender activist Mariah Lopez, 27, who lobbied for a new review of Johnson’s death. Lopez hailed Johnson, who died at 46, for her role in resisting police who raided the Stonewall Inn, an event that launched the gay rights movement in 1969.