the reason that there are two choices are because of people like him disengaging and not supporting a third choice

I think this is untrue, or at least not the major factor. First-past-the-post voting seems to result inevitably in the situation the US finds itself in, with two main parties with no significant differences on most major issues, where voting for a third party candidate causes a spoiler effect.

http://www.youtube.com/watch?v=s7tWHJfhiyo