Social media have become more and more relevant political communication arenas. Social media are used by various political organizations (Nitschke, Donges, & Schade, 2016), they have evolved to key territories for populist actors (Engesser, Ernst, Esser, & Büchel, 2016), and their importance in election campaigns as well as their influence on election results is highly debated (Groshek & Koc-Michalska, 2017). These trends seem to be in line with the mediatization of politics thesis, which states that the media and mediated communication are becoming increasingly important in politics and increasingly influencing political processes