2008: Skynet sends a second Terminator (this time modeled after Hillary Clinton) through time in order to kill Obama shortly before to the West Virginia primary.
I would actually like to see Hillary traveling back in time to '36, and it turns out that she hooked up with time traveling Obama, and they are McCain's parents. Then Obama is able to return to the future, while Clinton is trapped in the past, where she is left to raise McCain. And she's still around today, as "Roberta McCain"....helplessly watching her younger self's campaign implode around her. Of course, she can't do anything about it, or it would have grave consequences for the timeline.