Politics and advocacy increasingly take place on social media platforms. Interest groups are actively engaged, using these platforms to shape public issue debates and advance their policy agendas. Yet, less is understood about how interest groups use social media for networked activities and establish affiliations with one another for political purposes. This paper sheds light on how interest groups use social media to connect with other interest groups and contextualize their online networked behavior. Beyond messaging and connecting with the public, interest groups use social media as both an informational and social network. I discuss the ways interest groups create affiliations to enhance their engagement with the platform users, increase their visibility and validity, and cultivate a social and information network that extends beyond their positional camp. Interest groups form affiliations with other groups based on strategic, social, political, and informational decisions, and account for the “hype-orientation” and attention economy at work on social media. Using an original data set of interest group Twitter accounts, I present a networked measure of interest group online behavior using a variety of methods including, assortative measures, centrality measures, and exponential random graph models, to evaluate how interest groups connect on Twitter.
