Why do parties use moral rhetoric to explain and justify their policy positions to voters? Conceptualizing moral rhetoric as parties' attempts to represent voters' moral values, I argue that parties use moral rhetoric because it is a type of argumentation that is appealing to a broad set of voters, including both copartisans and non-copartisans. Specifically, I posit that preference for moral rhetoric is high among not only supporters of the party using moral rhetoric, but also among non-supporters who hold highly morally convicted attitudes about politics. Using original survey data from six countries (Australia, France, Germany, Switzerland, the UK, and the US), I present evidence in support of my argument. The finding that moral rhetoric is attractive to voters beyond the party base provides important nuance to existing claims that morality polarizes and tribalizes politics. The paper contributes to research on party competition, morality and politics, and representation.