Twenty-two-year-old Deronta Persons entered the plea on Friday in the death in March 2011 of 51-year-old Nahum Dalmace of New Castle.
The News Journal of Wilmington reports that Persons faces a minimum of 18 years in prison at sentencing in November.
Dalmace was shot and found in his crashed cab. He died three weeks after the shooting.
Information from: The News Journal of Wilmington, Del.