Sounds like a self-fulfilling prophecy to me. I agree that disinterested parties have a lot to gain from a probabilistic analysis, but someone who's working at

Sounds like a self-fulfilling prophecy to me. I agree that disinterested parties have a lot to gain from a probabilistic analysis, but someone who's working at the phone bank likely cares deeply about the cause and is convinced that their efforts can make a difference. At a macro scale, they do make a difference. It's precisely those kinds of actions which shift the overall probabilities regarding the outcome.