Despite a general consensus that citizen group supporters vary radically in their level of group activity, we know little about what factors “create” an activist. This paper asks: What factors determine which mode a supporter chooses? We seek to answer this question by examining socio-demographic correlates of participation and several “benefits” of participation using individual level survey data. This question informs a more central question: What factors separate the activist from the “regular” supporter? We find that those individuals best able to bear participation costs who also participate out of a sense of duty and who enjoy group participation most, are the most likely to opt for maximum participation. Our data support the conclusion that duty, commitment, and the desire for expressive benefits are capable of overwhelming the “free-rider” impulse. However, activists are not typical, comprising only a fraction of group membership. This means Olson, who would predict that few people would become activists, is right for most people most of the time.