This study investigates the effect of online political ads on party preference, and whether this effect is more pronounced for newer political parties and voters who are less politically knowledgeable and literate regarding online privacy. A mixed-method approach, combining Facebook browser tracking data and a four-wave panel survey, was adopted during the 2021 Dutch General Election campaign. The results showed that the number of political ads received from a specific party has a positive effect on both the propensity and choice to vote for that party. In addition, people with less political knowledge and online privacy literacy are more likely to be persuaded by online political ads. However, at the party level, there is no evidence indicating that the effect of political ads on party preference is stronger for new parties than for established parties. Overall, this study shows that voters can be persuaded via the frequency of exposure to online political ads, but the extent to which they are affected can vary.
