Bransford was born in Richmond, Missouri. As a child, Bransford had traveled the Mormon Trail with his family on their journey to California in 1864, stopping temporarily in Salt Lake City. In Plumas County, California, Bransford was a county assessor from 1886 to 1890 and served three terms as the county sheriff. He was elected to these positions as a Democrat.^{[citation needed]}

Bransford moved to Salt Lake City in 1899 and remained there permanently. In 1900, Bransford was elected the president of the Salt Lake Stock and Mining Exchange. In 1904, he joined Utah's anti-Mormon American Party, but remained a member of the Democratic Party.^{[citation needed]}

Bransford became the mayor on August 13, 1907, 11 days after Ezra Thompson resigned due to ill health and accusations of corruption. Bransford was unanimously elected by the city council as the replacement for Thompson. Bransford served out the remainder of Thompson's term and was elected mayor in the election of 1907. He was re-elected in 1909, and served until the end of his second elected term in 1911.^{[citation needed]}

As leader of the American Party, Bransford was considerably less vocal in his anti-Mormonism than his predecessor had been, and the leaders of the Church of Jesus Christ of Latter-day Saints were much relieved to have Bransford rather than Thompson leading the city where their church was headquartered.^{[citation needed]}

Bransford's most notable achievement as mayor was the creation of a walled red-light district in Salt Lake City, known as the "Stockade", which restricted the prostitutes of the city to working in the square block between 100 and 200 South and between 500 and 600 West.^{[citation needed]}

After Bransford left office, the American Party collapsed. He was a delegate from Utah to the 1912 Democratic National Convention and was a member of the Platform and Rules Committee.^{[citation needed]}

• List of mayors of Salt Lake City

• Jeffrey D. Nichols (2002). Prostitution, Polygamy, and Power: Salt Lake City, 1847–1918 (Urbana: University of Illinois Press, ISBN 978-0-252-02768-0)
• Hal Schindler, "Colorful Mayoral History Awaits Unprecedented Corradini Chapter" Archived 2016-12-02 at the Wayback Machine, Salt Lake Tribune, 1991-11-10, p. A1
• Hal Schindler, "The Oldest Profession's Sordid Past in Utah", Salt Lake Tribune
• John S. Bransford, politicalgraveyard.com