According to The Hollywood Reporter, John Spencer, the versatile, Emmy-winning actor who had a central role on the NBC White House drama The West Wing from its inception, has died. He was 58. Spencer died Friday of a heart attack at Olympia Medical Center in Los Angeles. He would have turned 59 on Tuesday.

Spencer had been sick with the flu for several days, according to his publicist, Ron Hofmann. The actor checked into the hospital Thursday and suffered a heart attack Friday morning, Hofmann said. Spencer's death leaves a major void in the story line of West Wing, where Spencer's character, Leo McGarry, had segued from his former role as chief of staff in the administration of Josiah Bartlet (the outgoing president played by Martin Sheen) to being the vice presidential candidate alongside the liberal Democrat Matt Santos, played by Jimmy Smits.

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