The (over-)promise of data-driven campaigning: Investigating dynamics...

Targeted political ads are often criticized for their potential to mislead and polarize voters. Yet, they might provide citizens with relevant content that could reengage the electorate with politics. Taking the less-studied upside of targeted political ads as a point of departure, this study examines whether increasing targeted political ads’ perceived congruence – a match between citizens’ party and issue preferences and the presented ad – promotes online and offline political participation. Theorizing dynamic change processes, we further hypothesized a spillover from online to offline political participation and potential algorithmic feedback mechanisms between online political participation and congruence perceptions. To test our model, we conducted panel studies during the Dutch general election 2021 (Study 1, N_T1 = 1,245, N_T2 = 792) and the German federal election 2021 (Study 2, N_T1 = 1,914, N_T2 =1,535, N_T3 = 1,303). Furthermore, in Study 2, we use a random intercept cross-lagged panel model (RI-CLPM), which gives novel insights into intrapersonal changes over time. Overall, we find that perceived congruence is positively associated with political engagement on- and offline (between-person relationship). However, there is limited support that perceived congruence fosters political participation over the course of a campaign (within-person effect). Furthermore, the evidence for algorithmic feedback mechanisms is mixed. Lastly, our results offer robust evidence that online political participation can be a gateway to offline political participation, at least early in the campaign.