How voters choose one out of many: a conjoint analysis of the effects of endorsements on candidate choice

Candidate endorsements affect the likelihood that people vote for a candidate since they reduce the efforts devoted to vote choices. However, the effects of endorsements from different sources remain under-explored. Furthermore, the effects of endorsements are believed to vary with the level of political sophistication, as voters with low sophistication are more reliant on such shortcuts, but it is unclear whether these differences are similar for different sources. We study the effects of endorsements from three different sources – family and close friends, networks on social media and Voting Advice Applications (VAAs) – on candidate favorability. We do so with a choice-based conjoint experiment embedded in a survey from Finland (n = 1021), where we also examine differences in effects across political sophistication (political interest, frequency of political discussions, internal political efficacy, party identification, and voting in the last parliamentary election). The results show that endorsements from VAAs and family and friends have positive effects while social media networks do not. We do not find systematic differences in effects across levels of political sophistication no matter how we operationalize it. This shows that it is important to consider the source of an endorsement to appreciate the effect, no matter who is the recipient.