The plan would involve Trump investing millions of his own money --perhaps $20 million or more -- in one or two outside groups about six months before their respective election days if Texas Senator Cruz or Ohio Governor Kasich stand for office again.
Trump Would Fund Super-PACs Aimed at Taking Down Cruz, Kasich - Bloomberg Politics - July 22, 2016
I would certainly hope that nearly two years from now, President Trump will have a lot more serious things on his plate than worrying about spending $20 million of his own money to fight against two GOP down ticket candidates.