Oklahoma politics from statehood through World War I was dominated by the Democratic Party , with the Republican Party and the Socialist Party vying to challenge the Democratic Party 's dominance . The 2nd Oklahoma Legislature included Oklahoma 's first black member , Republican A. C. Hamlin , but passed legislation that made it nearly impossible for African-Americans and seek elective office , which limited him to one term . In the 1910s , the Oklahoma Legislature included Socialists , but the only bill they sponsored that became law involved hunting . Socialists were also elected to local office and received the nation 's highest vote count per capita for the party 's candidate , Eugene V. Debs in 1916 . The Jim Crow Law in Oklahoma was struck down by the United States Supreme Court , but a special session was called by the Democratic governor and focused on voting laws that limited black voter participation . The Ku Klux Klan and the civil rights struggles of the World War I era came to Oklahoma in the 1920s , leading to the Tulsa race riot , lynchings and other violence . Following the practical destruction of the Socialist party in the aftermath of the Green Corn Rebellion , state politics became a two-party system that continued to exclude black voters
Tulsa race riot
Tulsa race riot
Politics of Oklahoma