Competing on commitment: How parties strategically make election pledges to gain credibility among the electorate

Election pledges commit parties to implement certain policies and provide certain outcomes after an election. Although parties get little reward from voters and lose flexibility, parties regularly commit themselves to certain policies by making these pledges. In this paper, I examine why parties commit to such a high extent. I argue that parties make pledges to signal credibility to voters, when the party is close to competing parties’ positions. Compared to other campaign statements, election pledges can make voters more confident that parties will act on their words, so a party with more commitments will ceteris paribus have an advantage over other parties with similar positions on an issue. I test my expectation by manually coding election manifestoes from parties in Denmark, United Kingdom, and United States from the last three decades to measure the extent to which each party makes commitments on an issue. I find support for my argument by showing that the share of commitments increases when the average positional distance to other parties on an issue decreases. My results are important for understanding how party competition can generate the policies of tomorrow.