Participation, Contestation, and the Electoral Connection in the One-Party South, 1930s–1960s

Between the New Deal and the Great Society, the representatives of the one-party Democratic South occupied a pivotal position in national politics. Often treated as a unified bloc, on economic issues Southern Democrats in Congress were in fact ideologically diverse, ranging from New Deal liberals to anti-statist conservatives. Though the distribution of Southern preferences often determined the set of feasible policies, scholars know relatively little about the sources of Southern ideological diversity. This paper examines the factors associated with the ideology of Southern members of Congress, particularly the patterns of competition and turnout in Southern Democratic primaries. I find that in addition to demographic factors like the urban and white percentages of the population, the size of the active electorate is positively related to the election of economically liberal members of Congress. The effects of participation and contestation were each moderated by the other: the liberalizing effect of a larger electorate was greater in contested constituencies, and the effect of primary competition depended on whether the electorate was relatively large (liberal) or small (conservative). These findings highlight the political heterogeneity within the one-party South and its con- sequences for the ideological balance of power in Congress.