In 1982, Earl ran for governor when Lee S. Dreyfus unexpectedly declined to run for re-election, and soon the Wisconsin Democratic Party's hopes of reclaiming the governor's mansion became very real. As head of the state DNR, Earl was well-received as a staunch defender of the environment and a problem-solver. Earl used that reputation to defeat former Acting Governor Martin J. Schreiber (1977–79) in the Democratic primary for governor. Earl went on to defeat the Republican candidate, Terry Jodok Kohler, in a landslide victory.