This represents the initial round of analysis on a new dataset. Comments/criticisms welcome, please contact the author for (potentially significant) updates before citing.


This paper presents an analysis of early data from the newly-launched Membership Communications Project (MCP). The MCP is a data-aggregation effort concerned with tracking the email practices of progressive advocacy organizations in American politics. Based on 2.5 months of data collection across 70 organizations (998 messages in total), the goal of the paper is twofold. First, the paper establishes the purpose behind and construction of the MCP dataset, offering an “annotated user’s manual” of sorts for interested members of the research community. Data collection will continue for at least six months, and the dataset is freely available to other researchers. Second, the paper uses the MCP email data to create two types of social network graph – an affiliation network of organizations and issue areas and a social network graph of the “strong ties” formed through joint outreach efforts between organizations. The analysis is preliminary in nature, but it strongly suggests that the new generation of internet-mediated organizations include issue-generalist “grazers” and issue-niche specialists. It also indicates that there is substantial variance between organizational email strategies, with no evidence of any overarching, thematic set of “best practices.”