He was cited by Box Office magazine as one of the top five stars of the future and the recipient of Photoplay's Gold Medal Award for 1972.

A Republican, he ran for the California State Assembly in 1998, losing the general election to Democrat Hannah-Beth Jackson.

In 2012 and 2014, he ran unsuccessfully for the U.S. House of Representatives in the 24th Congressional District; he lost the primary in 2012 to former lieutenant governor Abel Maldonado, and the general in 2014 to 16-year Democratic incumbent Lois Capps.

In 2012, Mitchum ran for the U.S. House of Representatives as a Republican candidate in California's 24th district (San Luis Obispo, Santa Barbara, and part of Ventura counties), challenging incumbent Democratic Congresswoman Lois Capps.

[3] In the June 5, 2012 primary, he came in third, behind Republican Abel Maldonado and Capps, and ahead of Independent candidate Matt Boutté.