Things can change on a hurry between exit polling and official reporting. The party has been engaged in a media narrative since day one and the polling numbers will be used when itís convenient to do so.
But they are transitory especially when it comes to Trump vs. Biden.
Coupla things that will wreck those poll numbers:
Republicans will be hauling Biden into criminal investigations over Burisma. Subpoenas are getting readied. Joes got dirt under his nails here.
He continues to mentally deteriorate on the trail. Debates may prove difficult for him going forward between Sanders or Trump, if he makes it.
Front runner status means his consummate insider record will become an issue regarding trade, equal rights, support for reactionary Supreme Court justices, trying to cut social security, etc..,
All of this and much more makes for a lot of drag on his numbers going forward. The left has been publicly ratf#cked by the party again. I donít think they will come out this time nor should they. Without that support I doubt his numbers will stand up to Trumps going down the road.