Fair play, @
Mert.
I know there will be comparisons to the Brexit vote, but 11 of the last 23 polls had Leave winning against a backdrop of long-held Eurosceptic views. There's been literally no indication from tracking polls, early exit polling, or early vote analysis to suggest this was going to happen. Obama has a high approval rating (mid-fifties) and the economy is going well - therefore you'd expect more acquiescence in a 'third term' - whilst you're running against the most unpopular candidate ever. He also had one (literally one) media endorsement worth anything. It's a huge upset against conventional wisdom.
It's a serious blow to the Obama legacy, such as it will be, as I suspect his executive orders / Obamacare could be repealed quite quickly.