Answer:
O. Robert La Follette.
Explanation:
Robert Marion La Follette was the 20th Governor of Wisconsin, active in office from 1901 to 1906. He then became a member of the US Senate and became a huge critic for the administrative policies of the US, both domestic and foreign.
While in office as the Governor, Follette helped set up direct primaries in the United States, implementing primary elections. He also supported the policy of tax reforms on corporations, the growth of trade unions, and even helped create referendum ideas, initiatives, and recall.
