 In 1960, Johnson sought a seat in the U.S. Senate. He defeated John Y. Brown, Sr. in the Democratic primary, but was unable to unseat Republican incumbent John Sherman Cooper in the general election. In 1961 and 1964, he was appointed to the state board of education. He served as a delegate to an assembly to revise the state constitution in 1964. In 1965, the University of Kentucky honored him with a Centennial Award and inducted him into its Hall of Distinguished Alumni. He died February 7, 1970 in Richmond, Kentucky, and is buried in Richmond Cemetery.
