If this 60% you are talking about is real and not just a number you have pulled out of the air (Which I believe it is) try to consider that the 60% might be a lot of Democrats who understand how much he is hurting the Republicans, and loving it. I look at him as being the Ross Perot of the 2016 election. Deja vu.
It was just a random figure as an example for my argument.
He is a very shrewd marketer and knows how to appeal to specific demographics. If he appeals to the anti-immigrant voters he gains "x" number of votes. Badmouthing immigrants costs him "y" votes. As long as x is greater than y he is winning. His actual opinion does not matter. He says whatever he thinks will get him the most votes. Alienating 40% of the voters is fine if he gets support of the other 60%.