Are American Politicians as Partisan Online as They are Offline? Twitter Networks in the U.S. Senate and Maine State Legislature

American legislatures have been idealized for past collegiality but are castigated in the present for partisanship in voting and cosponsorship. As legislatures move into new social media environments, are their online relations as partisan as their offline behaviors? To assess this question, this study analyzes thousands of Twitter posts, by, to, and between legislators in the saturated, professionalized social media environment of the U.S. Senate and the sparser, do-it-yourself social media environment of the Maine State Legislature. Social ties over Twitter involving legislators are found to be far less partisan than ties of shared voting and ties of shared cosponsorship. Rather, these politicians follow more complicated patterns of social media behavior depending on media presence and legislative context. Despite the strength of parties in legislatures, social context conditions the social behavior of legislators.