Jose Beltran was previously convicted of one count of second-degree murder and two counts of attempted murder for opening fire on Juan Vazquez and two co-workers Vazquez was driving home from work last August.
A bullet struck Vazquez in the head.
Superior Court Judge Clifford Klein, who sentenced Beltran on Friday, called the crime "a callous killing."
Authorities say Beltran began pursuing Vazquez's car after the 25-year-old deliveryman passed him at a stop sign.
At one point Vazquez pulled over to let Beltran pass but he opened fire instead.