Donald Trump CAN’T increase his fan base.
There is absolutely NOBODY out there who hasn’t made up his mind about Trump and may yet be won over. Nobody.
There’s a chance, however tiny, that there are people out there who don’t know much about Cruz (or Jindal or or Rubio), and who might like him if they learned more.
But Donald Trump (who, I keep telling you, is NOT running!) can’t possibly win over anybody who doesn’t already like him. If anything, people will learn that he’s flip-flopped on all the big issues, and will abandon him.