To be fair, Trump deliberately causes much of his publicity. Remember that he is an anti establishment figure in charge of the establishment. This is usually instant death for the anti establishment figure as they become the establishment.
Trump however is (IMO) keeping his support base onside by deliberately doing things to cause his political opponents to scream blue murder, which makes his supporters think that he's hurting the metropolitan rich as much as they have hurt people on low wages in manufacturing and service jobs over the last decade or so.
He can also manage damaging media stories by taking advantage of the media having the attention span of a goldfish and doing things that attract news stories and followups for weeks.
He is definately a lot more intelligent than a lot of people give him credit for, and i'm far from convinced that he's going to be out of office at the next election because people underestimate him so much. In fact, i'd hazard a guess that this is going to look very similar to his next election strategy pitched at everywhere other than cities:-
The media says how horrible I am, but you personally are better off. Your wages are higher because:-
A) i've kicked out as many illegal immigrants as I can and reformed immigration laws reducing competition for your jobs, so your wages have risen.
B) i've reduced taxes, thus increasing your employers income so they can afford to pay you more.
C) i've reduced taxes so that you keep more of your hard earned money.
D) The media lied to you about all of the above, look at your pay packet! If I get in them I will extend these tax breaks and you will continue to be better off. If my enemies get in, they are going to axe all of my work and you will be massively worse off. Vote Trump to make america great for hard working workers!
Personally, I think that stands a reasonable chance of winning, because the media is only really persuading the people who already hate trump that he can be safely underestimated.