Clifford Philip Case (16 April 1904 in Franklin Park, New Jersey – 5 March 1982 in Washington, D.C.) was an American lawyer and Republican Party politician who represented in the United States House of Representatives (1945–1953) and served in the United States Senate (1955–1979) as from the State of New Jersey.
Following his graduation from law school in 1928 he was admitted to the bar in 1928 and commenced practice in New York City. In 1938, Case was elected to the Common Council for the city of Rahway, New Jersey. He served in that capacity until 1942, when he was elected to the New Jersey General Assembly, where he served from 1943 to 1945. In 1944, case ran and won election to the United States House of Representatives, serving in the Seventy-ninth, Eightieth, Eighty-first, Eighty-second, and Eighty-third Congresses. Case resigned from his seat in the House on 16 August 1953, when he took up the position of president of the Fund for the Republic from 1953 to 1954.
In 1954, Case ran for the United States Senate. He was strongly anti-McCarthy and so was opposed by conservative elements within his own party. During the campaign a New Jersey newspaper quoted former Communist Party leader Bella Dodd as saying that Case's sister Adelaide was "an active member of several Communist front groups." It was later revealed, however, that the Adelaide Case in question was not the candidate's sister but a college professor who had died in 1948.
In the general election, he defeated fellow U.S. Representative Charles R. Howell by a very narrow margin. In the Senate, he complied one of the most liberal records of a Republican in the U.S. senate. He was re-elected in 1960, 1966 and 1972. Case won 22 votes for president at the 1968 Republican National Convention, losing the nomination to Richard Nixon.
Case sought a fifth Senate term in 1978, but lost the Republican primary to Jeffrey Bell, an anti-tax conservative. Bell went on to lose the general election to Bill Bradley. No Republican has been elected to represent New Jersey in the Senate since Case's last victory in 1972.
After leaving the Senate, Case resumed the practice of law with Curtis, Mallet-Prevost, Colt & Mosle, a New York law firm. Case also lectured at Rutgers University's Eagleton Institute of Politics. He died on 5 March 1982, in Washington, D.C. and was interred at the Somerville New Cemetery in Somerville, New Jersey.
His grandson, former Clinton Mayor Matthew Holt, was elected to the Hunterdon County Board of Chosen Freeholders in 2005.