I THINK many voters got tired of seeing the same kind of folks nominated for President, Romney, McCain, Biden, Harris, Bush, .... I think Obama seemed fresh and different, and he won of course. For some voters, there doesn't seem to be a difference between the two candidates, and they think neither is going to "fix things". So, they looked for someone very very different .... and I think we'd all agree we got him, twice now.
I'm from the camp that thinks a President doesn't make a lot of difference, nominations will be different, foreign policy can be rather different, maybe the marginal income tax rates get a smallish shift, maybe we run huge deficits,the CFR keeps expanding, ...the verbiage will be different, but The Machine keeps running the country, at least many think that, some call it the Deep State.
There is a persistent feeling the country is running down, and folks want somebody who can arrest that, and are willing to take a chance. Good luck.