Benjamin F. Stapleton attended National Normal University in Lebanon, Ohio, graduating with a law degree. Early in the 1890s, Stapleton went to live in Denver, and in 1899, he was admitted to the Colorado Bar. Stapleton enlisted for service in the Spanish-American War. At the conclusion of his war-time service, Stapleton returned to Denver to practice law and first became actively interested in politics, helping found the Veterans of Foreign Wars. On June 21, 1917, Stapleton married Mabel Freeland, with whom he had two children, Lois Jane and Benjamin, Junior. Stapleton's political career began in 1904 as police magistrate, where he remained until 1915, when President Woodrow Wilson appointed him postmaster. During his appointment, he oversaw the completion of the Denver Post Office building. After a brief stint in private law practice following his resignation in 1921, Stapleton defeated Dewey C. Bailey in Denver's mayoral election in 1923 and was re-elected in 1927.