Political Conspiratorial Beliefs are Likely Over-Estimated and Transitory

Prominent conspiracy beliefs, such as QAnon or 2020 Presidential Election beliefs, constitute a unique form of conspiracy theories that are often explicitly partisan, "politically instrumental conspiracy theories" (PICTs). PICTs can spread rapidly, quickly becoming consensus beliefs among partisan in-groups. But PICTs are not necessarily deeply held, rather primarily serving immediate instrumental partisan needs. We use novel survey list experiments to estimate the prevalence of QAnon and 2020 Presidential Election conspiracy theories in the United States. We find that standard survey techniques likely overestimate the prevalence of PICTs by a factor of $\sim$2. Over-reporting of PICTs is driven by right-wing media consumption (QAnon), and partisanship (2020 Presidential Election). Further, we find that PICT attitudes are heterogeniously related to engagement in political and pro-social behaviors. While the prevalence of PICTs is commonly over-estimated and the beliefs may be transitory, they can serve an instrumental role in the contemporary American electorate.