Inequalities in Online Representation: Who Follows Their Own Member of Congress on Twitter?

Members of Congress increasingly rely on social media to communicate with their constituents and other members of the public in real time. However, despite their increased use, little is known about the composition of members' audiences in these online spaces. We address these questions using a panel of Twitter users linked to their congressional district of residence through administrative data. We provide evidence that Twitter users who followed their own representative in the 115th, 116th, and 117th Congresses were generally older and more partisan, and live in wealthier areas of those districts, compared to those who did not. We further find that shared partisanship and shared membership in historically marginalized groups are associated with an increased probability of a constituent following their congressional representative. These results suggest that the efficiency of communication offered by social media reproduces, rather than alters, patterns of political polarization and class inequalities in representation observed offline.