Cho, Wendy and J. Gimpel, I. Hui (2013). Voter Migration and the Geographic Sorting of the American Electorate, Annals of the Association of American Geographers. 103 (4), 856-870. http://myweb.uiowa.edu/bhlai/workshop/gimpel.pdf
This article examines migration patterns within the United States of America through the lens of partisanship.
The authors claim that the geographic pattern of partisanship is spatially non-random. While people may not migrate with partisanship in mind, there are factors that correlate to partisanship. Employment opportunities, race, income levels, education and housing are main determinants in migrating, and do correlate to party association.
This study was conducted over a period of fours in seven different states: New Jersey, Maryland, Delaware, Pennsylvania, California, Oregon and Nevada. Voter registration files from 2004, 2006 and 2008 were collected and referenced to gather the data. These states were chosen because they represent two groups of adjacent states, register voters by party and have high-quality, accessible voter registration files.
The study found that more than half of people moved within their county. Democrats moved more frequently than Republicans, but they also comprised a larger share of the registered voters. The authors confirmed a theory that Democrats congregate in more urban areas, while more Republicans moved to suburbs or rural areas. The map below confirms this trend in Portland, Oregon.
|Republican migration out of Portland|
|Democratic migration to Portland|