Thomas Mitchell Campbell (April 22, 1856 – April 1, 1923) was Governor of Texas from 1907 to 1911.

Biography
Campbell distrusted monopolistic big business and sympathized with trade unions. He shared many of the reformist political views of, former Texas governor James Stephen Hogg. In 1897, Campbell resigned from the railroad and became active in Democratic party politics and at Hogg's urging, decided to run for governor.
Campbell was elected governor in 1906. In his two terms in office, 1907-1911, Campbell initiated a number of reforms involving railroad regulation, equitable taxation, and lobbying restrictions. The most significant legislation centered on prison reform, as Campbell's administration ended the contract lease system for inmates and implemented more humane treatment of prisoners. Under Campbell, many state agencies also came into being, including the Department of Insurance and Banking, the Bureau of Labor Statistics, the State Board of Health, and the Texas State Library.
Campbell returned to private law practice in Palestine but remained active in Democratic politics. In 1916, he ran unsuccessfully for the United States Senate. He died in Galveston and was buried in Palestine.