And I'd even say that he doesn't need to be negative at all.
At this point, all he needs to do is lay out his programs for the economy; law and order; foreign policy; and immigration. On each of those points, he has winning plans, and staying in the mud only makes it harder for him to break away cleanly. That's why they keep dragging him into the slop, and he can't seem to stay away. It's like an alcoholic with the phenomenon of craving.
Donald has to whip a very reluctant GOP into line if he expects to git-r-done in Washington. I am not sure this is such a huge negative.
Very well said