Race and Space: The Spatial Demography of U.S. Elections

Jonathan Rodden, a political scientist at Stanford, published a piece in the Washington Post this week with the provocative title "This map will change how you think about American voters — especially small-town, heartland white voters." He and his colleagues have put together a very nice data set of geospatial precinct level voting results from the 2012 presidential election, along with the demographics of the precincts--as best as can be done when the boundaries don't exactly line up. His takeaway is that small town America is not actually where Republicans live.

One of the most striking lessons from exploring these maps is that the red nonmetropolitan counties on election-night maps are internally heterogeneous, but always following the same spatial pattern: Democrats are clustered in town centers, along Main Street, and near the courthouses schools, and municipal buildings where workers are often unionized. They live along the old railroad tracks from the 19th century and in the apartment buildings and small houses in proximity to the mills and factories where workers were unionized in an earlier era.

 I looked at his maps and immediately drew the conclusion that race was a key factor. Minority groups tend to cluster near the centers of almost every city of any size in the U.S. Professor Rodden did not mention this in his article, however, and I had a good deal of difficulty accessing his maps online because they loaded very slowly. Perhaps that was because Emily Badger and Quoctrung Bui of the NYTimes Upshot section were busily tapping into the data to draw those same conclusions. The map below uses Rodden's data to track the increasingly strong relationship between population density and voting patterns. Democrats do better in the denser city centers and Republicans do better in the less dense suburbs. As a result of white flight over the years, the dense city centers have increasingly become ethnic enclaves, while the suburbs are predominantly white (although not as white as they used to be). These spatial demographic patterns are in play in the current presidential election, just as they were in 2012. The real question, though, will be voter turnout in the red and blue areas. We'll find out the answer pretty soon...