After Michigan gave up seven runs in the second game, Clarke came into the game as a pitcher and pitched the final six innings. He held the Milwaukee team scoreless for two innings, but he gave up eight runs in the sixth inning, two in the seventh and one in the eighth. Michigan lost the game 18-1. Clarke also appeared in two games against the Hamilton Club of Chicago in May 1899. Michigan won both games by scores of 4-3 and 6-1. During Clarke's two seasons as a baseball coach, the team compiled records of 15-6 and 14-5 and finished 2nd and 1st in the Western Conference. Clarke was also the coach of Michigan's all-freshman football team in 1898. In the fall of 1899, Clarke was admitted to the Illinois bar and joined the Chicago law firm of Church, McMurdy & Sherman. Clarke returned to Nebraska in 1900 and established a law partnership with Frank Crawford, a classmate from the University of Michigan who also served as Michigan's first football coach in 1891. They practiced law together as Crawford & Clarke from 1900 to 1905. In 1904, Clarke was elected as a Republican to the Nebraska House of Representatives. He was reelected to the same office in 1906. Clarke was the sponsor of a child labor bill that passed the Nebraska legislature and was signed into law in 1907. He was also active in the passage of a pure food law. In March 1907, Clarke was appointed as a Nebraska railroad commissioner by Governor George L. Sheldon, following a vacancy on the commission. He was elected to the position in a special election in the fall of 1907. He was elected to a full six-year term in 1910. Clarke worked from at least 1918 to 1920 as a traffic manager and attorney for the Omaha Grain Exchange. Clarke was a member of the Masons, the Elks, the Royal Arcanum, the Omaha Club, the Fontanelle Club, the Omaha Commercial Club, the Lincoln Commercial Club, the Lincoln Country Club and the Episcopal church. Clarke was married in September 1901 to Grace Louise Allen. They had three children, Allen Gordon Clarke, William Cleveland Clarke and Henry T. Clarke III. Clarke spent the last year of his life at the Emory John Brady Hospital, a psychiatric hospital in Colorado Springs, Colorado. He reportedly suffered from Alzheimer's disease. He died in Colorado Springs in March 1950 at age 74.