Clinton's RCP average in a 4-person race is only 44.4%. You've got to imagine the missing top of this graph. Picture an empty space that's larger than what you see here, which tops out at 45%:
That's more than 55% of voters who do not support Clinton, and you've got to figure a good portion of those who do support her only support her out of rejection of Donald Trump. In fact, that's the main argument her campaign is making for her. She also lays claim to all the liberals who loathed her in the primaries and wanted Bernie Sanders. We're headed into what could be a landslide victory for someone that almost nobody likes.
I'm searching for an up side to this. Perhaps it's bad to have a beloved President. Is Obama beloved? Yes, to a great extent he is. Here's his approval rating over time. It doesn't look that great, but I think we Americans are mostly liking and trusting him and, as a consequence, not getting as outraged about things that should be bothering us. The new President will not be loved and may very well be hated. And all the things we've let slide as we indulged the well-liked Obama are going to fall heavily into the lap of the new, loathed President who we're not going to cut any slack.
I'm trying to say there's some good in that: 1. We'll have to face reality (or something close to that), 2. We'll break out of our complacent funk and get back to our old tradition of sharply criticizing the President, 3. We'll stop looking to the President for spiritual uplift and pseudo-religious hope of salvation.