Date of Original Version
Whether Americans have “sorted” into politically like-minded counties and to what extent is hotly debated by academic and journalists. This paper examines whether or not geographic sorting has occurred and why it has occurred using a novel, dynamic analysis. Our findings indicate that geographic sorting is on the rise, but that it is a very recent phenomenon. In the 1970s and 1980s, counties tended to become more competitive, but by 1996 a pattern of partisan sorting had emerged and continued through the present. Results suggest this pattern is driven by Southern re-alignment and voting behavior in partisan stronghold counties. Lastly, we find evidence that migration can drive partisan sorting, but only accounts for a small portion of the change.
Lang, C., & Pearson-Merkowitz, S. (2014). Partisan Sorting in the United States, 1972-2012: New Evidence from a Dynamic Analysis. Political Geography, 48, 119-129.
Available at: http://dx.doi.org/10.1016/j.polgeo.2014.09.015