He succeeded Wesley Bolin as governor when Bolin died in office on March 4, 1978. Arizona does not have a lieutenant governor; the Arizona Secretary of State, if holding office by election, stands first in line in case the governor vacates his or her post. However, Rose Mofford, then secretary of state, had been appointed to her post and thus was not eligible to become governor according to the Arizona state constitution. Babbitt, as attorney general, was next in the line of succession, and thus served the balance of the term to which Raúl Héctor Castro had originally been elected in 1974. Babbitt was elected for a full four-year term later in 1978, and again in 1982. He did not run for a third term in 1986.