[3] He ran for the Senate from Nebraska in 1954 and won; subsequently, incumbent Hazel Abel resigned, and Curtis was appointed to the seat on January 1, 1955, getting a two-day jump on seniority.

[10] Curtis was loyal to the Republican Party, particularly supporting its anti-communist stances and fiscal conservatism, which included opposition to social programs such as the New Deal and the Great Society.

During the 1963 investigation of bribery allegations against Democratic Party organizer Robert Baker, Curtis supposedly leaked a secret memorandum to advance his own positions.

During the early 1970s, Curtis supported President Richard Nixon's Vietnam War escalation policy, and remained loyal to him throughout the Watergate Scandal.

[13] Following his retirement, Curtis moved to Lincoln, Nebraska, where he practiced law, served as an officer of the conservative lobby the American Freedom Coalition, and gave occasional interviews to the media.