The problem of trolls exemplifies the challenges of building democratic communities in the digital environment of social media. Distinguishing trolls from activists can be difficult; democratic theorists have yet to adequately address how to prevent the former while remaining open to the latter. In this article, I outline a theory of democratic politics that takes space as a central element in shaping democratic interactions. Using the work of John Dewey, I draw out two key characteristics of democratic space: boundedness and flexibility. Using these criteria, I then evaluate Kinja, Gawker Media's commenting platform, both before and after trolls attacked the site in 2014. I find that in altering its boundaries to successfully protect against trolls, Kinja introduced a new problem: a lack of flexibility that continues to affect the possibility for democratic discourse on the platform. I conclude by suggesting how this theory of democratic space might shape future research.