Mobilization effects using mail: Social pressure, descriptive norms, and timing

We use field experiments in Texas and Wisconsin to address voter mobilization and turnout by evaluating nonpartisan get-out-the-vote (GOTV) messages delivered via mail during 2010 gubernatorial campaigns. We manipulate three factors in the messages: social pressure, descriptive- and injunctive-voting norm consistency, and message timing. The results present an initial field-based confirmation that norm-consistent messages increase turnout; demonstrate significant message timing effects, which are mediated by state election rules; and indicate social pressure's effectiveness varies significantly more than previously found. These diverse findings suggest researchers place a greater emphasis on context when evaluating experiments and the effects of mobilization messages.