Honestly, I don't know.
We have the stupid electoral college system here in the US, where votes get proportioned by states. And those polls all show Clinton with a fairly decent advantage even if the popular vote is close.
But that's if the election took place today. When it comes to predicting the trends, no one has any clue. They can't figure out why anyone is voting for Trump in the first place (you can take from that what you like

).
In the end I think it will come down to who actually shows up at the polls. I think there are a larger than normal percent of Trump supporters who won't vote. A lot of them are trolls a la Milo Yiannopolis. They just want to piss everyone off, and they don't actually have to vote for Trump to do that. They can just say the voted for Trump. There are also a lot of anti-establishment types who are attracted to Trump, but they are so anti-establishment that they never vote.
OTOH, I think there are also a larger than normal percent of people who don't show up on polls who will vote for Trump. These include cranky old people who hate when people call them up and think it's none of your business asking them fool questions. And people who don't want to admit they like Trump because they don't want to be perceived as racists/imbeciles (some of them might actually be, some not).
How many mainstream Republicans will grit their teeth and vote for Trump vs gritting their teeth and voting for Clinton vs abstain? How many college kids will stick to their ideals and vote for a third party or abstain vs voting for Trump? How many blue collar union people will vote for Trump because they are worried about immigrants taking jobs vs voting for Clinton because Trump is anti-union?
Will there be more shootings? What about terrorists?
The thing most in Trump's favor is that he is untouchable. He's made every blunder in the book, been caught in lie after lie, no one knows what his policies are, he's insulted every other candidate and basically done everything you are NOT supposed to do. And it doesn't seem phase his supporters at all.
OTOH, Clinton has been in politics for a long time. And not just her, but her husband. So there are all sorts of things from the past that can be dredged up to hit her on. And she's not well-liked anyway.
So basically this gives Trump free license to just try to disrupt things in as many ways as he can. I think the more people see the election as a circus, or just start hating the whole thing, the more it suits Trump. Clinton has to play by the traditional rules to win. Trump has no rules.