Daniel Isaac J. Thornton (January 31, 1911 – January 19, 1976) was a United States cattle breeder and Republican politician who served as the 33rd Governor of the State of Colorado from 1951 to 1955.Daniel Isaac J. Thornton was born in Hall County, Texas, on January 31, 1911 and graduated from Lubbock, TX high school in 1929. He was very active in 4-H and was elected President of the Texas 4-H clubs in 1927.