Of all the available adjectives to describe Donald Trump, “scared” isn’t one that comes to mind.
Maybe not 'scared', as in shaking in his boots scared, but his every action telegraphs a profound lack of confidence in his own ability. He looks like a man who finds himself waaay out of his depth, and knows it.
And this seems to be increasing as it becomes more and more evident that he will not manage a first ballot win, and will go on to lose the nomination.