Sen. Robert F. Kennedy standing in front of a poster of his late brother, President John F. Kennedy, 1966. The photo appeared on the cover of Life magazine.
Robert Kennedy made his political debut in 1952, managing John Kennedy's Senate campaign. In 1960, he again assumed the position of campaign manager, for his brother's bid for the White House.
Kennedy served as attorney general in his brother's Cabinet, resigning soon after President Kennedy's 1963 assassination to run for the United States Senate from New York.
June 5, 2008 marks the 40th anniversary of Sen. Kennedy's assassination. (Bill Eppridge/LIFE/Time Inc.)