John Spencer (right) is best known as the actor who played savvy and powerful chief of staff Leo McGarry on "The West Wing." Spencer, 58, died of a heart attack Dec. 15. Earlier, on the show, the McGarry character had survived a heart attack. Spencer, who won an Emmy in 2002 for his performance as McGarry, had also played attorney Tommy Mullaney on "L.A. Law." He began his career as a teenager with a recurring role on "The Patty Duke Show"; his big break was playing Harrison Ford's sidekick in the 1990 movie "Presumed Innocent."