Thomas Coleman du Pont (December 11, 1863 – November 11, 1930) was an American engineer and politician, from Greenville, Delaware. He was President of the of E. I. du Pont de Nemours and Company, and a member of the Republican Party who served parts of two terms as United States Senator from Delaware. He was known by his middle name.

Early life and family
Du Pont was born at Louisville, Kentucky. He was a cousin of U.S. Senator Henry A. du Pont and great grandson of Eleuthère Irénée du Pont, the founder of E. I. du Pont de Nemours and Company. Du Pont attended preparatory school at Urbana University and earned an engineering degree at the Massachusetts Institute of Technology. While at MIT, he was initiated into the Sigma Chi fraternity.

Business career
Coleman du Pont started his career in the family's coal mines, the Central Coal and Iron Company, and soon pursued opportunities in street railways. In 1894, He began working as the general manager of the Johnson Street Rail Company in Johnstown, Pennsylvania.

With his cousins, Alfred I. du Pont and Pierre S. du Pont, Coleman bought out the family's explosives business in Delaware. He was president from 1902 until 1915, during which time he oversaw the acquisitions of more than one hundred competitors. He was a key player in the formation of the holding company, E. I du Pont de Nemours Company of New Jersey. In 1907, the DuPont Company was sued for antitrust violations and Coleman later sold off his stake of the business in 1914.

Coleman du Pont had control of the Hotel McAlpin, Claridge Atlantic City, Wallick's, and other American hotels. Together with Lucius M. Boomer, president of Boomer-du Pont Properties Corporation, Thomas Coleman DuPont owned a number of other hotels. In 1918, they purchased the Waldorf-Astoria Hotel in New York City, then in 1920 the Willard Hotel in Washington, D. C. and in 1925 the company purchased The Bellevue-Stratford Hotel in Philadelphia from the heirs of the founder, George C. Boldt.

In 1915 Coleman du Pont acquired control of The Equitable Life Assurance Society from J. P. Morgan and was responsible for the building of the Equitable Life Building in New York City, once the largest building in the city.

Political career
du Pont with Frank H. Hitchcock
Du Pont retired from business activities in 1915 and became involved in Republican Party politics, as a member of the Republican National Committee from 1908 until 1930. It was largely under his leadership that the Union Republicans and Regular Republicans came back together and built the modern Delaware Republican Party.

Du Pont was appointed to the U.S. Senate on July 7, 1921, to fill the vacancy caused by the resignation of U.S. Senator Josiah O. Wolcott. During this term, he served with the Republican majority in the 67th Congress. However, he lost his bid to complete the term in a special election on November 7, 1922. On the same day he also lost his bid for the full term to follow, in both instances losing to Democrat Thomas F. Bayard, Jr., a Wilmington, Delaware lawyer. He was elected to the U.S. Senate in 1924, defeating the incumbent Republican U.S. Senator L. Heisler Ball for the nomination, and going on to defeat Democrat James M. Tunnell, a Georgetown, Delaware lawyer. During this term, he served with the Republican majority in the 69th and 70th Congress, until health problems caused him to resign.

In all, Du Pont served two separate terms, one from July 7, 1921 until November 21, 1922, during the administrations of U.S. President Warren G. Harding, and the other from March 4, 1925 until December 9, 1928, during the administration of U.S. President Calvin Coolidge. The later years of his life were marked by his implication in the Teapot Dome scandal, and by lawsuits over various Florida real estate deals.

Death
Du Pont suffered from cancer of the larynx and died at his home, 808 Broome Street, Wilmington. He was buried in the Du Pont de Nemours Cemetery in Greenville, Delaware.