When Do Politicians Use Populist Rhetoric? Populism as a Campaign Gamble

Why do some politicians employ populist rhetoric more than others within the same elections, and why do the same politicians employ more of it in some elections? Building on a simple formal theoretical model of two-candidate elections informed by the ideational approach to populist communication, we argue that the initially less popular political actors are more likely to use populist rhetoric in a gamble to have at least some chance of winning. To test the empirical implications of our argument, we construct the most comprehensive corpus of U.S. presidential campaign speeches (1952-2016) and estimate the prevalence of populist rhetoric across these speeches with a novel automated text analysis method utilizing active learning and word embedding. Overall, we show the robustly greater use of populism among the presidential candidates with the lower polling numbers regardless of their partisanship or incumbency status.