Rough Terrain: Spatial Variation in Campaign Contributing and Volunteerism


  • Thanks to Brady Baybeck, David Darmofal, Brian Gaines, and Scott McClurg for helpful comments.

Wendy K. Tam Cho is Associate Professor in the Department of Political Science and the Department of Statistics, and Senior Research Scientist at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, Department of Political Science, 240 Computing Applications Building, 605 E. Springfield Ave., Champaign, IL 61820 ( James G. Gimpel is Professor of Political Science, University of Maryland, 3140 Tydings Hall, College Park, MD 20742 (


We examine spatial patterns of mass political participation in the form of volunteering and donating to a major statewide election campaign. While these forms of participation are predictably associated with the political and socioeconomic characteristics of the precincts in which the participants reside, we find that these statistical relationships are spatially nonstationary. High-income neighborhoods, for example, are associated with stronger effects on participation at some locations more than at others. By using geographically weighted regression (GWR) to specify local regression parameters, we are able to capture the heterogeneity of contextual processes that generate the geographically uneven flow of volunteers and contributors into a political campaign. Since spatial nonstationarity may well be a rule rather than an exception in the study of many political phenomena, social scientific analyses should be mindful that relationships may vary by location.