Ultimately, electoral democracy is about governments doing what citizens want. However, considerable evidence shows that parties influence citizens’ preferences. Most studies on party influence rely on experimental designs that present participants with parties’ positions. The disadvantage of experiments is that many citizens are already aware of those positions, thus underestimating party influence. Very few studies assess reactions to real changes in party positions, which avoids this limitation. We break new ground by assessing the impact of changes in coalition governments, which lead parties to express different positions for reasons that are partly exogenous to elite and mass preferences, on partisans’ attitudes. Using panel data from the German Longitudinal Election Study (GLES), we leverage a major coalition change by Angela Merkel in Germany in 2013. We find that this change influenced the preferences of partisans of the coalition parties. Our findings have significant implications for how we think about democratic representation in multi-party contexts.