Political mobilization in the laboratory: The role of norms and communication

Many field experiments have shown that political mobilization increases voter turnout, with personalized strategies considerably outperforming widely administered ones. Despite the abundant evidence, there is no systematic explanation of what drives citizens' response to mobilization. In this paper, I propose and experimentally test in the laboratory a theoretical framework that investigates the psychological mechanisms underlying mobilization in both partisan and non-partisan settings. I conjecture that material mobilization efforts should increase participation because of reciprocity concerns. The transmission of normative appeals through interpersonal communication should have a similar effect by making a group norm salient. The results from two experiments show that the combination of a mobilization effort with a normative appeal leads to a significant and substantial increase in participation in both settings. Using content analysis, I show that this interaction effect is due to the way normative appeals are perceived when the sender is in charge of mobilization.