From Pledge to Poll: Investigating the Impact of Campaign Promises on Party Alignment

Political parties regularly make campaign promises to attract voters prior to elections. This paper explores whether such electoral pledges allure the voters that they target. By utilizing children’s date of birth in a regression-discontinuity design, we measure the effect of a campaign promise made by the German conservative party to expand social benefits. The results show that the campaign promise increased alignment with the pledge-making party by 12.7% among eligible beneficiaries. The alignment effects are stronger among supporters who traditionally align with left-wing platforms and/or individuals with lower economic security. The promise had no mobilizing effect on inactive voters. Finally, we document that the promise effect is transitory as re-alignment among recipients disappears shortly after the pledge is fulfilled. The paper provides strong causal evidence that campaign promises related to social benefits are a successful strategy to temporarily attract voters from competitor parties.