Robert Marion "Fighting Bob" La Follette, Sr. (June 14, 1855 – June 18, 1925) was an American Republican. He was a Senator from Wisconsin from January 2, 1906 until his death on June 18, 1925. He ran for President in 1924, but lost. If La Follette won he would have been the seventh President to die in office. He is thought to be one of the greatest Senators of American History.