Liberal democratic theory conceptualizes elections as competitions over policy, in which candidates promote clearly formulated policy platforms. Yet many campaigns in modern democracies lack a strong policy focus. Instead, some candidates spent notable time and effort to advertise valence issues, such as their personal characteristics and abilities. So far we have no good explanation why some do and other don’t. This paper presents a formal model of when we should expect candidates to run a valence campaign and when not. Based on Riker’s idea of herethetics, our model produces predictions in line with the dominance principle: candidates who have a valence advantage should run a campaign that focuses on valence, rather than on policy. The model’s predictions are tested in the 2008 US Congressional Elections. Valence advantage is empirically quantified from a voter model that is based on survey data. We find that candidates tend to broadcast fewer policy-related TV ads if they have a valence advantage over their opponent.
