Candidate debates have a rich history and remain integral to contemporary campaign strategy. There is, however, no evidence that they affect voter behavior. The scarcity of political information in the developing world offers an attractive testing ground. Using experimental variation in Sierra Leone, we find that public debate screenings build political knowledge that changes the way people vote, which triggers a campaign expenditure response by candidates, and fosters accountability pressure that disciplines the subsequent spending of elected officials. We parse the effects of information conveyed about policy versus charisma, and find that both matter. The results show how political communication can trigger a chain of events that begins with voters and ultimately influences policy.