John Spencer (December 20, 1946 – December 16, 2005) was an American actor. He is best known for his role as Leo McGarry on the NBC political drama series The West Wing . His performance on the show earned him a Primetime Emmy Award in 2002.

Spencer died of a heart attack in a Los Angeles hospital on December 16, 2005, four days before his 59th birthday.[4] At Spencer's private funeral, his West Wing castmate, Kristin Chenoweth, sang the musical number "For Good" from the Broadway musical Wicked. Spencer's remains were interred at Laurel Grove Memorial Park in his hometown of Totowa, New Jersey.

At the time of his death, Spencer had filmed two of the five West Wing episodes that were in post-production: "Running Mates" and "The Cold".[7] Spencer's death was later written into the show's seventh and final season, in which McGarry was said to have died of a heart attack on election night. Coincidentally, McGarry had also suffered a near-fatal heart attack in the show's sixth season. Spencer's name remained in the opening credits throughout the remainder of the show.