Ideological polarization in a decentralized party system: Explaining interstate differences

Abstract

During the past decade scholars have noted growing ideological polarization between Democratic and Republican Party elites in the United States. This trend has occurred in a party system traditionally characterized as decentralized. This paper examines whether the trend towards partisan polarization noted by scholars at the national level has affected state party systems in similar ways. Are some state party systems more polarized than others? The paper uses a classification scheme of state party systems developed by David Mayhew to try to explain interstate differences in partisan polarization. The paper concludes that states with political environments that supported pragmatic and non-ideological traditional party organizations are less polarized in the modern era than states without such environments.

Notes

1 This period includes the first three national election cycles (2000, 2004, 2008) of the 21st century, a period in which scholars of both national and state-level politics have noted growing ideological polarization in the party system (Abramowitz and Saunders, 2008; Jacobson, 2004; Layman and Carsey, 2002). The period is also long enough so that a representative sample of state party platforms could be obtained.

2 As previously mentioned, the states that are the basis for the state platform data are less representative of Mayhew's categorization than the states used in the survey. Mayhew (1986, p. 196) classified 60% of the states as “1,” 12% as “2,” 2% as “3,” 10% as “4,” and 16% as “5.” In Table 1 (platform data), the breakdown is 77% (1), 10% (2), 0% (3) 7% (4), and 7% (5). In Table 2 (survey data), the breakdown is 67% (1), 6% (2), 0% (3), 12% (4), and 15% (5). The strong-organizational states are clearly underrepresented in the platform data.