Probably not. Its not impossible, but it is highly improbable. The polls are misleading at the moment for several reasons, not the least of which that the Democrats have not unified yet.
The most telling poll at this time are favorability polls. Trump has historically low favorability numbers. He may have a very small base that rabidly supports him, but virtually everyone else in the Republican Party is, at best, unexcited about him (at worst, they just don't like him). This election will probably see record low turnout on the Republican side. Meanwhile, every time Trump opens his mouth and says something bigoted or misogynistic, he is galvanizing the opposition.
Meanwhile, Clinton is running a very artificial but also very clever campaign. She is playing it by the book and safe. It isn't going to excite a lot of people but at the same time she has Trump to do that for her. Moreover, she isn't going to make mistakes or gaffes that rally Republicans against her. It is why both President Bushes are not going to endorse Trump. It is why most Republican leadership will stay out of this fight. The name "Clinton" doesn't scare Republicans like it once did. She won't excite people by talking about nationalized health care like Sanders, but she also won't rally the opposition by doing so either
Because of this, Trump is trying to rally the base by using silly little names like "Crooked Hillary." But as I posted last week, most Americans don't buy into that nonsense. In fact, the only ones who do are Trump's hardcore base (who really aren't a statistically significant voting demographic). Even if they do buy into it, they don't care. Its the advantage of being in the public spotlight for 30 years. Your skeletons are out in the open and most are apathetic to said skeletons by this point.
So in the end, Clinton will simply play it safe and let Trump do the dirty work for her. Every time he opens his mouth, he ensures more Democrats come to vote and more Republicans stay home.
The great irony of a "winner" like Trump is that he is not only going to cost the Republicans what could have been a very winnable presidency (with the right candidate). He is going to cost them the Senate as well. Possibly even the House.