A 61-million-person experiment in social influence and political mobilization

Political mobilization messages delivered to 61 million Facebook users during the 2010 US congressional elections directly influenced political self-expression, information seeking and real-world voting behaviour of millions of people and their friends, with social transmission occurring mainly between close friends and having a greater effect than the direct effect of the messages themselves.

A 61-million-person experiment in social influence and political mobilization | Litlas