What are the dynamics of partisan rhetoric in presidential campaigns? (How) has presidential candidate partisanship changed over time? Analyzing a comprehensive dataset of party-related statements in presidential campaign speeches over the 1952–2012 period, we show that Democratic and Republican candidates have taken distinctive approaches to partisanship. Overall, Democratic candidates have been partisans, while Republicans have largely refrained from partisan rhetoric on the campaign trail. However, this difference has narrowed substantially over time, due to a dramatic decline in the partisanship of Democratic presidential candidates. We argue that Democratic and Republican candidates have adopted different campaign strategies that reflect both enduring party differences and changing political contexts. Though naturally inclined to partisanship, Democratic candidates have adopted more conciliatory strategies primarily in response to growing public antipathy toward partisan rancor. In contrast, Republicans’ tendency toward more conciliatory rhetoric has been reinforced by political developments discouraging partisan campaigning.