British Journal of Political Science

Research Article

Pressed into Party Support? Media Influence on Partisan Attitudes during the 2005 UK General Election Campaign

Heinz Brandenburg and Marcel Van Egmond*


This study reassesses the ability of the mass media to influence voter opinions directly. Combining data on media content with individuals’ assessments of British political parties during the 2005 general election campaign allows a test of newspapers’ persuasive influence in a way previously considered a ‘virtual impossibility’. Utilizing repeated measures from the 2005 BES campaign panel, multilevel regression analysis reveals significant impact of partisan slant not just on the evaluation of the party mentioned but also on evaluations of its competitor(s). The strongest evidence of direct media persuasion is provided by the finding that variation in slant over the campaign drives how undecided voters evaluate the incumbent government party, even when controlling for a newspaper's average partisan slant.

(Online publication December 16 2011)


* Department of Politics and International Relations, University of Aberdeen (email:; and Amsterdam School of Communications Research, University of Amsterdam, respectively. The authors are listed in alphabetical order. The authors would like to thank Robert A. Johns, Cees van der Eijk, Amanda Hosking, Bernhard Wessels and other participants of the WAPOR conference in Berlin in 2008, as well as participants of EPOP conferences in 2007 and 2008, and this Journal's three anonymous reviewers for their helpful comments and suggestions. An online appendix with supplementary tables and replication data is available at