Have his book and the AH genre become more popular, maybe have him write magazine articles and newspaper columns on the side, make his name well known, and have a few of his opinions seen as cutting edge, and have one in particular touch on an issue/event that makes him seen as a visionary/authority.
Have him drafted as a third party cannidate, and by use of grassroots and social media, gets enough support to make it to the debates, where he tears both cannidates a new one. Wins in November in a squeaker.