Police said the boy is recovering from a gunshot wound to the leg at Memorial Medical Center, but his injuries don't appear to be life-threatening.
Officers found the boy wounded on Thursday afternoon on Hartridge Street. Investigators said he was campaigning for the Democratic senator ahead of the Georgia runoff election. He was at the front door of a home when someone fired through the closed door.
Police found Jimmy Paiz in the home, arrested him and took him to Chatham County Jail. He's charged with aggravated assault and aggravated battery.
Police are still investigating but law enforcement said there is no indication the shooting was politically motivated.
Warnock grew up in Savannah and graduated from Sol C. Johnson High School. Neither the senator nor his campaign had publicly commented on the incident on Friday morning.
Investigators ask anyone with information to call the Violent Crimes Tip Line at 912-525-3124 or CrimeStoppers at 912-234-2020.