Those six points represent independent voters who will vote for Trump in 2020 instead of the Democratic candidate.
Since the Mueller report came out nearly 25% if the independent voters have expressed they planned to not vote for Democrats in 2020 due to their obvious pushing of a fabricated collusion narrative which has disgusted these voters. I expect this number to only grow in the upcoming weeks -- especially after the release of the complete redacted Mueller report.
Your moron won because of 80000 votes after the Comey letter and BernieBros sitting out, if you think its gonna happen again when his only achievement being not indicted by his own DOJ without delivering on anything else is hilarious.
A 2% shift is enough to put this old demented fart back in his nursing home where he can bitch and whine.