摘要：We examine three alternative explanations for national policy shifts surrounding critical elections. We examine evidence for cohort, turnover, and partisan effects. Data for all congresses are used, and four critical elections-1828, 1860, 1896, and 1932-receive particular attention. The cohort and turnover hypotheses as explanations for critical election policy shifts are not supported. However, support for the partisan dominance hypothesis is strong. Political party membership and strength, rather than an influx of congressional newcomers with different socialization and characteristics, is associated with major policy swings.
