President Harry S. Truman vetoed the Act, but Congress overrode the veto on June 23, 1947, with 20 of the 45 Democratic Senators and 107 of the 188 Democratic Representatives joining with Republicans to override the veto. It is in the platform of all major U.S. labor unions to call for the repeal of the Act, especially Section 14 (b), and at times this has been reflected in the platform of the Democratic Party. However, the only time this has ever seemed likely was when the Democrats had a huge majority in both houses of Congress following the Republican electoral disaster of 1964. Even then, the repeal bill passed 221–203 in the House, but the two-thirds majority it needed in the Senate was never attained, partly because of long filibustering by Republicans such as Senate Minority Leader Everett Dirksen. Labor allies failed to break the filibuster, and the repeal bill was withdrawn by the Democratic Majority Leader, Mike Mansfield, in 1966.