DelBello was Mayor of Yonkers, New York and was the first Democrat to become Westchester County Executive prior to being elected lieutenant governor in 1982. He ran for the Democratic nomination for lieutenant governor as the running mate of then Mayor of New York City Ed Koch. Koch endorsed him as a running mate believing he would help Koch with suburban voters. DelBello faced Ambassador Carl McCall, the running mate of then Lt. Gov. Mario Cuomo, in the Democratic primary.
DelBello won his primary and Cuomo defeated Koch for the governor's nomination. The Cuomo/DelBello ticket then won the 1982 general election. Del Bello had little interaction with Cuomo during his time in office. He focused on his role as President of the New York State Senate during his time as lieutenant governor, along with projects of his initiation and Cuomo's assignment. These projects included emergency management, local government and economic development.
DelBello resigned from the lieutenant governorship in February 1985 saying that he was bored and that Cuomo did not give him enough to do. He went into private business after leaving the State government. In 1994 he unsuccessfully sought a State Senate seat from Westchester.
In December 2006, DelBello was appointed by the Westchester County Association, a business advocacy group, as head of a Property Tax Reform Commission, in an effort to retain economic vitality in Westchester County. 
1982 New York State Democratic Ticket
- Governor: Mario Cuomo
- Lieutenant Governor: Alfred DelBello
- Comptroller: Raymond F. Gallagher
- Attorney General: Robert Abrams
- U.S. Senate: Daniel Patrick Moynihan
Edwin Gilbert Michaelian
|Westchester County Executive
1974 - 1982
Andrew Patrick O'Rourke
|Lieutenant Governor of New York
1983 - 1985
Warren M. Anderson
Acting Lieutenant Governor