Article Wedge-issue dynamics and party position shifts: Chinese exclusion debates in the post-Reconstruction US Congress, 1879–1882 Jungkun Seo University of North Carolina, Wilmington, USA Abstract Even when the stakes of party-building are high, political parties often find their members divided over a key policy position. In post-Reconstruction America, the hot-button issue of excluding Chinese immigrant workers strengthened Democratic cohesion while splitting the ‘party of Lincoln’. Previous research has not completely investigated the role of party competition and cohesiveness in paving the way for passage of the Chinese exclusion laws. In this investigation of the legislative politics of banning the Chinese from 1879 to 1882, it is found that cross-pressured members sometimes facilitate party transformation. The evidence demonstrates that partisan responses to potential wedge issues are a previously unnoticed source of explanation of eventual party position changes. Keywords Chinese exclusion laws, party position change, rank-and-file members, wedge issue Paper submitted 4 June 2009; accepted for publication 15 September 2009 Corresponding author: Jungkun Seo, Department of Public and International Affairs, University of North Carolina, Wilmington, NC 28403, USA. Email: seoj@uncw.edu Party Politics 17(6) 823–847 ª The Author(s) 2010 Reprints and permission: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1354068810376184 ppq.sagepub.com 823