American Journal of Political Science
The public agglomeration effect: Urban–rural divisions in government efficiency and political preferences
2025-12-11
Why and when do cities vote for the left? The emergence of the urban–rural divide in the United States in the 1930s is inconsistent with canonical theories of cleavages. This paper introduces an explanation: agglomeration effects. The provision of government services is more efficient in urban environments because of nonrivalries, economies of scale, and access costs. If the public sector in cities is more efficient, and voters face a trade‐off between taxation and government spending, urban voters support more spending. When redistribution is salient, one should observe an urban–rural electoral divide. As predicted by a formal model, more‐urban locations faced lower costs of providing public services and shifted toward the Democrats as the party implemented the New Deal. In addition, urban voters were more supportive of government spending. In the United Kingdom, the urban–rural divide also accompanied the rise of redistributive politics. Agglomeration effects influence preferences for redistribution and create political cleavages.