I can't imagine what kind of coalition he could assemble. I don't know if it would win, but if he takes whatever position his data tells him, the only obvious thing that would sink him would be his lack of authenticity. Imagine a candidate that always had an appealing take to a slim to large majority on whatever issue (for people that don't know too much about the issue).
In the previous 2016 race, HRC was perceived as inauthentic and lost. DJT was perceived as authentic to a substantial fraction the right (not the media class, though that has changed with the direction of the wind) and inauthentic to the left.
This is all hypothetical of course, he has to be one of the most unlikeable people in ages, and the reception to his “I identify with you, middle Americans” tour really solidified that feeling.