Social networking sites (SNS) currently boast more than half a billion active users worldwide, the majority of which are young people. With notable exceptions, few studies have ventured into the growing political realm that exists on these sites. This study expands research on SNS by examining both what encourages people to express themselves politically in this realm, and what effects such expression may have on classic questions of political participation. We test the proposition that political use of SNS among teens offers a new pathway to their political participation using hierarchical linear regression and panel data analysis. Results demonstrate that political SNS use strongly impacted both levels of and growth in traditional political participation during the 2008 election.