The Conditional Effects of Microtargeted Facebook Advertisements on Voter Turnout

Facebook advertisements are widely used in modern political campaigning and have come under tremendous scrutiny for their perceived ability to impact elections. However, there is limited evidence as to their effectiveness on voting behavior. An experiment conducted in Texas during the 2018 U.S. Midterm elections demonstrates that longitudinal exposure to issue-oriented Facebook ads may impact turnout, but that effects are conditional on an alignment of message, audience, and electoral context. Despite the large sample (N = 871,479) there is no detectable main effect of advertisements on turnout. Only individuals in competitive congressional districts assigned to receive ads about abortion rights and women’s healthcare exhibited a significant increase in predicted turnout (1.66pp relative to a control group); effects were concentrated among female voters. Three other message conditions had no impact on turnout.