Published online by Cambridge University Press: 18 May 2016
To what extent do political campaigns mobilize voters? Despite the central role of campaigns in American politics and despite many experiments on campaigning, we know little about the aggregate effects of an entire campaign on voter participation. Drawing upon inside information from presidential campaigns and utilizing a geographic research design that exploits media markets spanning state boundaries, we estimate the aggregate effects of a large-scale campaign. We estimate that the 2012 presidential campaigns increased turnout in highly targeted states by 7–8 percentage points, on average, indicating that modern campaigns can significantly alter the size and composition of the voting population. Further evidence suggests that the predominant mechanism behind this effect is traditional ground campaigning, which has dramatically increased in scale in the last few presidential elections. Additionally, we find no evidence of diminishing marginal returns to ground campaigning, meaning that voter contacts, each likely exhibiting small individual effects, may aggregate to large effects over the course of a campaign.
Ryan D. Enos, Associate Professor, Department of Government, Harvard University, 1737 Cambridge Street, Cambridge, MA 02138 (renos@gov.harvard.edu). Anthony Fowler, Assistant Professor, Harris School of Public Policy Studies, University of Chicago, 1155 East 60th Street, Chicago, IL 60637 (anthony.fowler@uchicago.edu). Both authors contributed equally. The authors thank Scott Ashworth, Rich Beeson, Chris Berry, David Broockman, Ethan Bueno de Mesquita, Peter Enns, Susan Fiske, Rayid Ghani, Trey Grayson, Don Green, Andy Hall, Hahrie Han, Eitan Hersh, Greg Huber, Scott Jennings, Bob Kubichek, Mary McGrath, Liz McKenna, Ryan Meerstein, Zac Moffat, Ethan Roeder, Gaurav Shirole, John Sides, Aaron Strauss, Will Howell, and conference participants at ASU, Oxford, and SPSA for helpful comments and insights into the 2012 presidential campaigns. To view supplementary material for this article, please visit http://dx.doi.org/10.1017/psrm.2016.21