On November 7, 1978, Durenberger was elected to complete the unexpired term of Senator Hubert H. Humphrey, whose position had temporarily been filled by Humphrey's wife Muriel. He was reelected in 1982 and again in 1988, serving from November 8, 1978 to January 3, 1995, as he did not for reelection in 1994. He had been the chairman of the Select Committee on Intelligence Ninety-ninth Congress. Durenberger was succeeded by Rod Grams.
Durenberger was unanimously denounced by the Senate on July 25, 1990 for unethical conduct relating to outside income.
SenatorDurenberger began his lifelong commitment to public policy reform as Chief of Staff to Governor Harold LeVander of Minnesota in 1966, when Medicare, Medicaid, and the Great Society's myriad of categorical health, welfare, and social programs were being launched in Washington.
During his Senate career, David Durenberger chaired the Intergovernmental Relations Subcommittee, led President Reagan's New Federalism effort in 1982, was a 14-year member of the Advisory Committee on Intergovernmental Relations, and served as Vice Chair of the Pepper Commission in 1989-1990.
SenatorDurenberger was also a member of HHS Secretary Otis Bowen's Medicare Catastrophic Committee, the Congressional Bio Ethics Committee, the National Infant Mortality Commission, and the Congressional Advisory Committee to the Office of Technology Assessment.