Duvall's political views are variously described as libertarian or conservative. He was personally invited to Republican President George W. Bush's inauguration in 2001. In September 2007, he announced his support for Republican Presidential candidate Rudy Giuliani. Duvall worked the floor at the GOP's 2008 national convention and, according to an August 29, 2008, MSNBC article, Duvall narrated most of the videos for the convention. In September 2008, he appeared onstage at a John McCain–Sarah Palin rally in New Mexico.