Obama's Third Term?
A US president can currently not run for more than two terms (8 years), so the eyes are of course firmly on Donald Trump, and Hillary Clinton as the next presidential candidates.
However!! 
If there were any kind of disaster (earthquake, or even a collapse of the economy) Obama could declare Martial Law, cancel the elections, and remain the president indefinitely. Even an election scandal could leave Obama in power for longer.
So, under those circumstances, Obama could well be in charge for some time to come.
Of course it ultimately doesn't really matter who wins, as any president (Democrat, or Republican) will just continue to do the bids of those who are really in charge (USA Inc).
Just throwing it out there...