This article explores the Electoral Discrimination thesis, according to which voters tend to discriminate against minority candidates. The free-list PR system used in Swiss elections—which allows voters to cast negative preference votes against candidates they do not want to support—offers a unique opportunity to test this thesis. Specifically, we analyze the relationship between immigrant-origin candidates bearing non-Swiss names and the negative preference votes allocated by voters to single candidates. Using a novel research strategy, based on election data stemming from our analysis of real ballots cast in the 2014 local elections in the Canton of Zurich, the article shows that candidates with non-Swiss names incur a significant electoral penalty. The effects of Electoral Discrimination are stronger, however, among supporters of parties from the Right and Center-Right. Interestingly, candidates bearing non-Swiss but Western names do not fare better than candidates with names of non-Western origin. We argue that our results have important implications for the comparative literature interested in electoral systems and minority representation.