I think he may lose some of his base from the right who follow politics, because he doesn't seemed to have drained much of the swamp and his focus is still on foreign policy issues too much, afghanistan, saudi arabia, NK..although he hasn't started any new wars just yet.
Knowing he is going to lose some voters, he might try and shift more to the centre, cultivate a softer image, although I can't see there is much room for him to reinvent himself. But if the democrats go for a candidate that middle america can't stomach then Trump might gain votes as he'll be seen as the least bad option again.
It'll likely be decided by the 'feeling on the street' if people feel that things are improving they'll give him another chance to carry on, I don't think it will be the media's support deciding who wins, they're now seen as out and out impartial and so have lost some of the public's trust they use to enjoy.
I suppose there is a possibility of people being so sick and tired of the political soap opera that they vote to get rid of trump [by voting for someone like biden], just so life can go back to relative normal
a bit like here in the UK with Brexit, the media and politicians/pundits trying to prevent brexit have been like a dog with a bone, and it seems the only way to get them to shut up is by the Uk officially remaining nothing else will do it
Also apparently it is very rare for an incumbent to lose the 2nd term election...