Voter volatility has become a hallmark of Western democracies in the past three decades. At the same time short-term factors-such as the media's coverage of issues, parties, and candidates during an election campaign-have become more important for voters' decisions. While previous research did look at how campaign news in general affects electoral volatility in general, it has omitted to explicitly test the mechanisms underlying these effects. Building on theories of agenda setting, (affective) priming, and issue ownership, the current study aims to explain why certain news aspects lead voters to switch their vote choice. We theorize it is the visibility of a party, the evaluation of a party, and the attention for issues owned by a party that primes voters to switch to a certain party. We use national panel survey data (N = 765) and link this to an extensive content analysis of campaign news on television and in newspapers in the run up to the 2012 Dutch national elections. The results show that issue news leads to vote change in the direction of the party that owns the issue. Even stronger is the effect of party visibility on vote switching. Our results, however, find the strongest support for the effect of party evaluations on vote change: More favorable news about a party increases switching to that party.
Keywords campaign news, content analysis, media effects, panel data, voting behaviorIn the past three decades the number of floating voters in Western democracies has increased considerably. The linkages between parties and citizens are of declining importance (Dalton & Wattenberg, 2000) and voters make more independent political choices instead of relying on traditional loyalties (Van der Meer, Van Elsas, Lubbe, & Van der Brug, 2013). As a consequence, citizens switch more often between parties than they did before, not only between elections, but also during election campaigns. With the decline in voter loyalty, sociological determinants have lost much of their predictive power (Dalton, 2013 Marks, 1999; Van der Meer et al., 2013) and results are scattered. Some report positive correlations between media use and volatility (Baker et al., 2006;Forrest & Marks, 1999), while others find a negative relationship (e.g., Bybee et al., 1981) and some find no effect (Dassonneville, 2011). Although these studies give insight into the effect of media use, the effect of media coverage is understudied.More recent studies have investigated whether different types of campaign coverage, most notably issue news and contest or strategic news, have an effect on individual-level vote switching (Adriaansen, Van Praag, & De Vreese, 2012;Takens, 2013). Adriaansen and colleagues (2012) found that issue news can induce voter uncertainty, whereas strategic news decreases voter uncertainty. This voter uncertainty would subsequently spark electoral volatility. In contrast, the study by Takens (2013) showed that voters become volatile in response to contest news, while issue news leads to stability in vote preferences. In this stud...