Complex sentence: When Wendell Anderson resigned the governorship to become a U.S. Senator in 1976, Olson, as the president of the State Senate, became the lieutenant governor; we would serve from December 29,1976, to January 3,1979.
Split into simpler sentences: When Wendell Anderson resigned the governorship to become U.S. Senator in 1976, Olson, as the President of the State Senate, became the lieutenant governor. He was Lieutenant Governor from December 29,1976, to January 3,1979.