Online political adverts: The effect of disclosures and opportunities for clandestine campaigning

Abstract The use of digital technology has become an increasingly prominent feature of election campaigns. While many of those using online tools are familiar partisan actors, many others are not. As concerns about electoral transparency have grown, policy makers have moved to implement regulation designed to help citizens recognize the identity of campaigners. In this paper, we test the rationale behind such regulations by asking how disclosures on online adverts—both informal badging and formal imprints—affect evaluation by UK voters. Using experimental survey design, we test the reactions of participants to real Facebook adverts, labeled as originating from both partisan and apparently non‐partisan sources. Across three experiments, we consistently find evidence to support concerns about what we term “clandestine campaigning”; a phenomenon whereby apparently non‐partisan groups can receive a more favorable reception for incongruous partisan advert content than overtly incongruous partisan‐badged campaign material.