Francesco Cali, 53, was found with multiple gunshot wounds to the torso, the NYPD said.
A law enforcement official confirmed to CNN that the victim was a high-ranking member of the Gambino crime family and is believed to be the acting boss.
Police responded to a 911 call Wednesday night of an assault in front of the home in the New York borough of Staten Island.
EMS responded to the scene and transported Cali to Staten Island University North where he was pronounced dead.
Police say there are no arrests and the investigation is ongoing