Does the mass media affect the dispersion of the policy positions of political parties? In this article it is argued that the mass media polarize parties' policy positions because vote-seeking strategies are more viable if party policy positions are clearly communicated to the electorate and because a vote-seeking strategy corresponds with parties taking a distinct policy position away from the median. Hence, the main hypothesis is that party policy position dispersion is larger with more mass media penetration. In order to test this argument, a novel dataset on party positions and mass media penetration in 267 Danish municipalities in 2004 is utilized and a new measure of the dispersion of policy positions in multiparty systems is constructed. The analysis corroborates the article's main hypothesis.