I don't think Gene Tunney did. His son John Tunney was elected to the Senate from California in 1970. Gene Tunney and Jack Dempsy both campaigned extensively for him. Tunney defeated the former movie star, George Murphy.
Terry Marsh ex jr welter champ ran for election as a uk mp. This is after he got away with allegedly shooting Frank Warren
Max Schmelling became and corporate Director of Coca Cola in Europe (not politics I knowm but high in the public sector)