Porter J. McCumber (February 3, 1858 - May 18, 1933) was a United States Senator from North Dakota. Born in Crete, Illinois, he moved with his parents to Rochester, Minnesota the same year. He attended the common schools and taught school for a few years, and graduated from the law department of the University of Michigan at Ann Arbor in 1880. He was admitted to the bar and commenced practice at Wahpeton, Dakota Territory in 1881. He was a member of the Territorial house of representatives in 1885 and a member of the Territorial senate in 1887. He served as State's attorney of Richland County from 1889 to 1891 and was elected as a Republican to the U.S. Senate in 1899. McCumber won reelection in 1905, 1911, and 1916 and served from March 4, 1899, to March 3, 1923; he was an unsuccessful candidate for renomination. While in the Senate, he was chairman of the Committee on Manufactures (Fifty-seventh Congress) and a member of the Committee on Pensions (Fifty-eighth through Sixty-second and Sixty-sixth and Sixty-seventh Congresses), the Committee on Indian Affairs (Fifty-ninth Congress), the Committee on Transportation Routes to the Seaboard (Sixty-third through Sixty-fifth Congresses), and the Committee on Finance (Sixty-seventh Congress).
McCumber resumed the practice of law in Washington, D.C. and was appointed by President Calvin Coolidge in 1925 as a member of the International Joint Commission to pass upon all cases involving the use of the boundary waters between the United States and Canada, in which capacity he served until his death in Washington, D.C. in 1933. His first interment was in the Abbey Mausoleum, adjoining Arlington National Cemetery; the remains were removed and reinterred in unknown location.