Attempting to capitalize on the gains made during World War II, many labor liberals feared a resurgence of racism and anti-Semitism that threatened to derail prospects for increasing union influence and advancing democracy in the postwar period. To counter the threat of demagogic appeals to workers, Jewish labor organizations and their allies launched a multipronged campaign “to tell biased people that the climate of opinion was against them” and “make people afraid to express overtly their bigotry.” This campaign drew on the insights of an influential network of social scientists, intergroup relations professionals, union and faith community leaders, and labor educators determined to quash the potential rise of domestic fascism with the countervailing force of a powerful union movement and an activist government. In consultation with social scientists and experts on mass persuasion techniques, they recruited a talented group of creative artists to produce posters, cartoons, and comics aimed at bringing their message to a working-class audience. This article reviews the assumptions that guided the climate-of-opinion campaign; examines the imagery, language, and messages artists used in their attempts to counter prejudice among rank-and-file trade unionists; and assesses the impact of these efforts. The mixed results of these activities underscored the serious challenges faced by labor liberals seeking to change entrenched attitudes of racial privilege and supremacy within the unionized working class.