Vaccinating across the aisle: using co-partisan source cues to encourage COVID-19 vaccine uptake in the ideological right.

Overcoming the COVID-19 pandemic in the United States will require most Americans to vaccinate against the disease. However, considerable research suggests that a significant proportion of Americans intend to forego vaccination, putting pandemic recovery at risk. Republicans are one of the largest groups of COVID-19 vaccine hesitant individuals. Therefore, identifying strategies to reduce vaccine hesitancy within this group is vital to ending the pandemic. In this study, we investigate the effectiveness of messages from co-partisan sources in reducing vaccine hesitancy. In a large (N = 3000) and demographically representative survey, we find that exposing "Middle-of-the-Road" partisans to pro-vaccine messages from co-partisan source cues reduces vaccine hesitancy. However, for those who identify as "Strong" or "Weak" partisans, we find no statistically significant differences in vaccination intentions when exposed to pro-vaccine messages from co-partisan sources. We conclude by discussing how our findings are helpful for vaccine communication efforts.