IF your very candidacy and identity rest on your supposed talent for victory, can you survive a defeat?

Can you continue to call yourself a winner if you’ve been a loser — and if “loser” is your favorite way of closing the book on someone, your final word, the workhorse in your brimming lexicon of slurs, exiting your mouth so reflexively that it’s essentially your exhalation, your carbon dioxide: “loser,” “loser,” “loser.”

Donald Trump has a problem that the other candidates for the Republican nomination don’t. He’s put an obstacle in his path that they haven’t. He doesn’t merely assert dominance. He claims something close to omnipotence. (Remember that laughable physician’s report?)

Neither his image nor his ego leaves any room for a setback, any allowance for second place. And as Iowa draws near and several polls suggest the strong possibility that Ted Cruz will finish ahead of him there, it’s time to talk about what that would mean for a self-enamored emperor who pretty much insists on his own perfection — and who has built his brand on it.