Bettmann / CORBIS

When Robert Byrd, then a state legislator from West Virginia, threw his hat in the ring for the U.S. House election in 1952, his opponents brought up a hat he had worn a decade before: the hood of the Ku Klux Klan. Byrd acknowledged his 1942-43 Klan membership as well as his roles as a Klan recruiter (or "Kleagle") and local chapter leader (or "Exalted Cyclops"). Despite a letter indicating that his interest in the Klan continued after 1943, Byrd won the House election and went on to win a Senate seat in 1958.

In 2006 Byrd became the longest-serving Senator in U.S. history, but he has never managed to fully erase his association with one of the nation's most reviled hate groups. In his 2005 memoir, Robert C. Byrd: Child of the Appalachian Coalfields, he wrote, "It has emerged throughout my life to haunt and embarrass me and has taught me in a very graphic way what one major mistake can do to one's life, career, and reputation."

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