Electoral College and voted for re-election of Abraham Lincoln. In 1868, Parker won a six-year term as judge of the Twelfth Missouri Circuit. Parker was nominated for Missouri's 7th congressional district on September 13, 1870, backed by the Radical faction of the Republican party. He resigned his judgeship and devoted his energy to his campaign. Parker won the election after his opponent withdrew two weeks prior to the vote. Parker was elected as a Republican to the United States House of Representatives of the 42nd and 43rd United States Congresses, serving from March 4, 1871, to March 3, 1875. He was the caucus nominee of his party for United States Senator in 1874. The first session of the 42nd Congress convened on March 4, 1871. During his first term, Parker helped to secure pensions for veterans in his district and campaigned for a new federal building to be built in St. Joseph. He sponsored a failed bill designed to enfranchise women and allow them to hold public office in United States territories. He also sponsored legislation to organize the Indian Territory under a territorial government. Parker was again elected to Missouri's 7th district in the forty-third Congress. A local paper wrote of him, "Missouri had no more trusted or influential representative in ... Congress during the past two years". In his second term, Parker concentrated on Indian policy, including the fair treatment of the tribes residing in the Indian Territory. His speeches in support of the Bureau of Indian Affairs gained national attention. In 1874, Parker was the caucus nominee of the Republican Party for a Missouri Senate seat. But, the political tide had shifted in Missouri; it seemed unlikely that the legislature would elect him to the Senate, so he sought a presidential appointment as judge for the Western District of Arkansas. Federal judicial service On May 26, 1874, President Grant nominated Parker as Chief Justice of the Utah Territory to replace James B. McKean. At his own request, Parker was instead nominated by President Ulysses S. Grant on March 18, 1875, to a seat on the United States District Court for the Western District of Arkansas. It had been vacated by Judge William Story, who resigned under threat of impeachment for allegations of corruption. Parker was confirmed by the United States Senate on March 19, 1875, and received his commission the same day. He served in this position