The American for Democratic Action (ADA) was established by Joseph Rauh in 1947. Rauh's main objective was support the advancement of liberal causes. Members included Eleanor Roosevelt, Walter Reuther, Hubert Humphrey, Chester Bowles, Edgar Ansel Mowrer, Felix Frankfurter, Philip Graham, Arthur Schlesinger, John Kenneth Galbraith, Joseph P. Lash, Francis Biddle and David Dubinsky. In 1948 ADA selected civil rights as its main issue and tried to persuade the Democratic Party and the Republican Party to support civil rights legislation.

Harry S. Truman shared the views of ADA and his Fair Deal proposals included legislation on civil rights, fair employment practices and opposition to lynching. When Truman won the Democratic Party nomination, Southern Democrats formed the States' Rights Democratic Party (Dixiecrats) and Strom Thurmond was chosen as its presidential candidate. He won 1,169,063 votes but came a poor third to Harry S. Truman (24,105,812).

In the 1950s and 1960s Hubert Humphrey was the main ADA figure in Congress. Elected as vice-president in 1964, Humphrey was able to influence the decision by Lyndon Baines Johnson to support the Voting Rights Act (1965) and the Immigration Act (1965).

Hubert Humphrey won the Democratic Party presidential nomination in 1968 but was defeated by Richard Nixon, the Republican Party candidate. However, membership of the American for Democratic Action continued to grow and reached 75,000 in the early 1970s.