National Centre of Competence in Research (NCCR) Challenges to Democracy in the 21 st Century Working Paper No. 45 Reinforcing Spirals of Negative Affects and Selective Attention to Advertising in a Political Campaign Christian Schemer Institute of Mass Communication and Media Research University of Zurich Andreasstrasse 15 CH-8050 Zurich, Switzerland Phone: +41 44 635-2074 Fax: +41 44 634-4934 ch.schemer@ipmz.uzh.ch October 2010