ObjectiveThough candidates for political office use their campaigns to appeal to voters, they are unable to do so uninterrupted. Prior research suggests that they must respond to the advertising strategies employed by their opponents when determining their own strategies. How does this responsiveness vary across the campaign cycle?MethodsI test how general election television advertising responsiveness varies over the course of the campaign cycle using data from 256 U.S. Senate and gubernatorial contests.ResultsThe results of my analyses show that candidates' overall, negative, and (to an extent) issue‐based advertising strategies become less informed by their opponents' strategies as Election Day approaches.ConclusionsThese findings suggest that candidates use the early stages of their campaigns to find effective general advertising strategies and become less responsive to their opponents once they have done so. In other words, campaigns appear to stay on message to a greater extent as the campaign unfolds.