“Gimme All Your Planks, or I’ll Take These Voters Elsewhere”
Campaigning to the Median Voter or Mobilizing the Base?
The Politics of Interest Group Influence on Political Party Platforms
Gina Yannitell Reinhardt, Texas A&M University
Jennifer Nicoll Victor, University of Pittsburgh
1
Prepared for the 67th Annual Meetings of the Midwest Political Science Association
Chicago, Illinois April 2-5, 2009
Overview
We use a game theoretic model to explain the conditions under which political parties will
incorporate interest group positions onto the party platform. We test the formal model using
content analysis of 1996, 2000, and 2004 DNC party platforms and platform hearing testimony.
Abstract
Downs predicts that presidential candidates will positions their platforms at the median. What
does this mean for party platforms? Are we to expect them to be placed at the median as well, or
farther toward the poles, in order to pander to party loyalists? We investigate these questions
theoretically, formally, and empirically, and argue that parties view interest groups as a means to
mobilize voters, while interest groups view parties and their platforms as a means to articulate
interests. A formal theoretical model derives the conditions under which parties would choose to
diverge from the median and articulate an interest group’s position in its platform, and an
empirical analysis further shows that parties give platform concessions to ideologues positioned
away from the median, to groups that offer a credible threat of exit to the opposition party, and to
groups that can credibly claim to mobilize voters. Both models account for a group’s ability to
mobilize voters, including size, party loyalty, and ideology. Data are derived from content
analysis of Democratic Party platforms and platform hearing testimony from interest groups in
1996, 2000, and 2004. Results show that interest groups can capture parties and their platforms
and mold the platform to reflect their views. Parties are compliant because they rely on groups
to help turn out voters.
The authors wish to thank Malory Grossman, Kaitlyn Karsin, Kyle Craig, Alecia Dyer, Jana
Stec, DaeJoong Kim, and the Democratic National Committee for providing documents and
research assistance.
1
Author order is alphabetical. Both authors have contributed equally to the final product of this paper.
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