Elmer Stiles Watson (June 19, 1908 – November 24, 1971) was an American military officer and politician who served as majority leader of the Connecticut State Senate from 1957 to 1959. Following graduation from high school, he took a job at his brother's insurance agency. He also joined the Connecticut National Guard and served with the United States Army in World War II. He remained with the Connecticut National Guard after the war and served as its commanding officer from 1949 to 1951.