Television viewer’s impressions of political candidates during a public speech can be based on the candidates’ verbal (e.g., the issues they are talking about, tone, rhetorical strategies), visual (e.g., gestures, facial expressions), and vocal (e.g., speech rate, frequency) behavior. Following two-process models of information processing (e.g., the elaboration likelihood model; ELM), we assume that the relative importance of the three communication channels depends on viewers’ political involvement. Compared to politically involved viewers, uninvolved viewers rather use heuristic information processing which relies on peripheral cues like nonverbal (especially visual) message elements. This suggests that verbal information will be more important for involved viewers whereas visual information will be more important for the uninvolved. In this study, we test this assumption by using an innovative research design. We combine a second-by-second content analysis of the use of 17 verbal, visual, and vocal message elements during the televised debate in the 2005 German National Election between Gerhard Schroeder and Angela Merkel (independent variable) with a second-by-second continuous response analysis (CRM) of 72 viewer’s impressions during the debate (dependent variable). Using elements of time-series and regression analysis, we calculate the relative influence of the message elements during each of the 5.500 seconds of the debate. Viewers’ involvement was measured by survey questions before the debate and by the frequency viewers used their CRM-dials during the debate. Later, it was recoded into three groups (low, medium, and high involvement). Our analyses show that verbal communication had by far the strongest influence on viewers’ impressions in all of the three groups. Nevertheless, we find an independent influence of visual and vocal communication going beyond the effects of verbal communication. Concerning Schroeder, the effect of visual communication almost linearly increased when involvement decreased. Concerning Merkel, the findings did not yield a clear picture.
