In 1847, he was chosen as one of Grant County's delegates to the 2nd Wisconsin Constitutional Convention. The constitution was ratified by a referendum in May of 1848, and, that fall, Orsamus was nominated by the Whig Party as their candidate for Congress in Wisconsin's 2nd congressional district. In the November general election, Cole defeated his opponents, Democrat A. Hyatt Smith and Free Soil candidate George W. Crabb, and earned a seat in the 31st United States Congress. In Congress, Cole sided with the anti-slavery Whigs and refused to support the fugitive slave provisions of the Compromise of 1850. He ran for re-election in 1850, but was defeated by Democrat Ben C. Eastman. He resumed the practice of law in Potosi, but, in 1853, stood on the consolidated Whig and Free Soil ticket as their candidate for Attorney General of Wisconsin. The Whig and Free Soil ticket was defeated in nearly all of the statewide races that year, and Cole again returned to his law practice.
Supreme Court
Following their defeat in 1853, Whig and Free Soil remnants went on to form the new Republican Party. In the 1854 elections, the new Republican Party was very successful and captured a majority of the Wisconsin State Assembly. That winter, they selected Cole to be their candidate against incumbent Associate JusticeSamuel Crawford in the April 1855 Supreme Court election. Cole defeated Crawford, largely because of his opposition to the fugitive slave laws, and took office the following June. He was re-elected to six-year terms in 1861, 1867, 1873, and was then re-elected to ten-year term in 1879. In November 1880, Cole was appointed by Governor William E. Smith to fill the vacant Chief Justice role created by the death of Justice Edward George Ryan. He was elected to a full ten-year term as Chief Justice in April 1881. Justice Cole served thirty six years and seven months on the Wisconsin Supreme Court, and was the longest-serving justice in the history of that court until he was surpassed by Chief Justice Shirley Abrahamson in 2013. At the end of his term in 1892, he retired to Milwaukee, Wisconsin, where he died on May 5, 1903. He was interred in Forest Hill Cemetery, in Madison, Wisconsin.
Personal life and family
He married his first wife Julia A. Houghton in 1848. They had two children, Sidney, who lived to adulthood, and Orsamus, who died as an infant in 1853. Julia died in 1874. He married his second wife, Roberta C. Noe Garnhart, the widow of John H. Garnhart, on January 1, 1879, at Madison, Wisconsin. She died June 17, 1884. His former home, now known as the Carrie Pierce House, is listed on the National Register of Historic Places.
