Party affiliation: Republican
Was city attorney and continued to practice law until 1865. Presidential elector on Fillmore ticket, 1852. Member Illinois House of Representatives, 1856, 1860-1861, 1872, 1873-1874 (speaker, 1861, 1873).
Member 39th to 41st Congresses (1865-1871). Appointed, by President Lincoln, 1862, with George S. Boutwell and Charles A. Dana to pass upon accounts of the United States quartermaster and commissary officers. Chairman Illinois delegation Republican National Convention, Philadelphia, 1872, and placed General Grant in nomination for the Presidency.
Governor of Illinois, 1876-1883, resigned. United States senator, since 1883.