COVID-19 Vaccination Rates Are Lowest among Political Outsiders in the United States

Vaccine hesitancy is a critical barrier to widespread vaccination uptake and containment of the COVID-19 pandemic. In the United States, vaccines have become politically polarized, with high rates of vaccine hesitancy observed among Republicans. In contrast to prior research focusing on partisan gaps, we investigate vaccination attitudes and uptake among a group overlooked in prior research: those who are eligible to vote but did not register in the presidential elections. Drawing on nationally representative and longitudinal survey data from April 2020 to October 2021, we show that this group – whom we call “political outsiders” – represents about 16% of the U.S. population. They had the lowest vaccination rate (47%) by 2021 October, significantly lower than Republican (65%), Independent (76%), and Democratic voters (88%). Further, we find that political outsiders are less likely to trust physicians compared to other partisan groups. Because the sources they trust differ from partisans, existing public health messaging may be less likely to reach them successfully. Finally, we find that political outsiders experience more socio-economic hardships and are less integrated into society. Hence, our results underscore the importance of targeted efforts to reach this highly vulnerable population.