Why did the electorate swing between parties during the Great Depression?

The Democratic Party's electoral success during the 1930s has long intrigued politicians and scholars. To gain new insight into that success, this paper examines the striking heterogeneity in county-level support for Roosevelt. Even though the Depression's effects and the New Deal's benefits were famously widespread, only some parts of the country responded with large and durable partisan shifts. One reason is that several factors, including pre-New Deal economic hardship, Dust Bowl conditions, and New Deal spending, appear to have had effects that were largely transitory (i.e., faded by 1940). A complementary reason is that swing electorates can, and did, swing both ways. By contrast, several other variables - notably economic and demographic factors discussed in the previous literature - are related to relatively durable shifts. Finally, heterogeneity in marginal responses may have mattered greatly to national-level Democratic success. By demonstrating which factors were transitory and which were more durable, this paper illuminates the New Deal Realignment and, more generally, the influence of economic conditions and distributive policy on voter behavior.