Trump has tremendous party VOTER support, all his rallies are overflowing with people...
and
he attracts most independents and a significant number of Democrats too (after all, many of his policies are quite liberal and he does NOT appear, at least, to be a crook or 24/7 liar like Hilliary)
He'll change, but it will be a natural change and it won't be sudden. In hindsight, looking back a few months, it will be a remarkable change in presentation.
Trump's public/rally presentation is a self-created caricature. He will slowly drop that, and the public will start to see more of how he deals with issues and conflict when he is in charge. The caricature is to get people to put him in charge. Before the election, he will be acting as if he is in charge.