1. Bristol & Levi have a ginormous political rally of a wedding.
2. Something dramatic happens on Thursday morning to keep Palin from attending the debate.
3. Palin has a "health scare" and she has to bow out.
4. from tx_cronopio : some sort of event will be manufactured to declare martial law and postpone the election.
5. and finally, the scariest theory of all, a theory from lapsedmodernist : the GOP orchestrates a heroic and brutal death for Palin's son who is fighting in Iraq. This enables her to step down, grief stricken, and also fuels a sense that the war is "just" and we must keep fighting and thus McCain wins.