This study argues that urbanization changed the relationship between candidates' occupation and their electoral success. To identify the causal effect of local variation in urbanization, we exploit exogenous changes in the boundaries of electoral constituencies in the 1928, 1932, and 1936 French parliamentary elections. We find that urbanization reduced the electoral success of lawyers—who had historically dominated electoral politics—while benefiting employees and workers. This effect was concentrated on the left of the political spectrum, whereby left-wing employees and workers displaced left-wing lawyers.