I think something we all need to keep in mind is Trump is not bleeding voters because of bad policy decisions. Maybe some will defect because of his rhetoric. If anything, independents and Democrats who have not drank the cool-aid, and voted for Hillary in 2016 are probably going to vote for Trump.
The pollsters have to keep it close because it is entertaining and keeps the voters interested.
This is actually a sad commentary. Trump talks like someone does who is used to getting stuff done. For all Reagan's statesmanship and bearing as a philospher king, that is what he was. He was a good thinker and a good leader, but he was not a guy who just want off and got stuff done. It didn't matter so much then, but we have decades of swamp rot that has set in under Bush, Clinton, Bush and Obama.