In this paper we investigate how online counter-discourse is designed, deployed and orchestrated by activists to challenge dominant narratives around socio-political issues. We focus on activism related to the UK broadcast media's negative portrayal of welfare benefit claimants; portrayals characterised as "poverty porn" by critics. Using critical discourse analysis, we explore two activist campaigns countering the TV programme Benefits Street. Through content analysis of social media, associated traditional media texts, and interviews with activists, our analysis highlights the way activists leverage the specific technological affordances of different social media and other online platforms in order to manage and configure counter-discourse activities. We reveal how activists use different platforms to carefully control and contest discursive spaces, and the ways in which they utilise both online and offline activities in combination with new and broadcast media to build an audience for their work. We discuss the challenges associated with measuring the success of counter-discourse, and how activists rely on combinations of social media analytics and anecdotal feedback in order to ascertain that their campaigns are successful. We also discuss the often hidden power-relationships in such campaigns, especially where there is ambiguity regarding the grassroots legitimacy of activism, and where effort is placed into controlling and owning the propagation of counter-discourse. We conclude by highlighting a number of areas for further work around the blurred distinctions between corporate advocacy, digilantism and grassroots activism.