At the 1948 Democratic National Convention , Truman attempted to unify the Northern delegations with a vague civil rights plank in the party platform . He was upstaged by liberals like Minneapolis Mayor Hubert Humphrey , who convinced Truman and the convention to adopt a stronger civil rights plank . In response , many of the delegates from Alabama and Mississippi walked out of the convention . Unfazed , Truman delivered an aggressive acceptance speech attacking the 80th Congress , labeling it the " Do Nothing Congress . " For his running mate , Truman accepted Kentucky Senator Alben W. Barkley after his preferred candidate , Justice William O. Douglas , turned down the nomination
1948 Democratic National Convention
1948 Democratic National Convention
Presidency of Harry S. Truman