The National Committee to Defeat the Mundt Bill AKA "NCDMB" (1948-1950) was an American organization that sought to oppose passage of the Mundt-Nixon Bill and subject of a 15-page report of the House Un-American Activities Committee, two of whose members were US Representatives Karl E. Mundt and Richard M.

[4][5][6][7][8][9][10] On June 1, 1948, Henry A. Wallace supporters visibly "took command" of a march on Washington to stop the Mundt-Nixon Bill from passing the Senate.

[11] In early June 1948, the bill died in the US Senate as the 1948 United States presidential election season commenced with conventions.

[14] On December 7, 1950, HUAC issued a 15-page Report on National Committee to Defeat the Mundt Bill: A Communist Lobby.

At that time, HUAC's senior investigator was Louis J. Russell and director of research Benjamin Mandel.