Just about the time I think Donald Trump has made the single public utterance that dooms his campaign, the polls surprise me.

He’s been brash, tasteless and thoughtless. He’s crossed so many lines of good behavior, it’s as if those lines never existed in the first place.

The latest, though?

He made fun of a fellow Republican presidential candidate’s appearance. The other person also happens to be the only woman running in the GOP primary field, Carly Fiorina.

He talked about Fiorina’s face and asked “Would you vote for that?” Trump said the next day or so that he was referring to her “persona.”

Sure, Donald.

I learned long ago, perhaps when I was a boy, that there are two aspects about someone that are off-limits: their name and their appearance.

I got kidded a lot as a kid about my name. It’s an ethnic name and some folks found it hard to pronounce. So, they’d poke fun at my name. I didn’t get it a lot, but I got ribbed about it some of the time.

As for my appearance, if my fellow junior high or high school pukes made fun of my looks, they did so behind my back.

If Trump — the GOP “front runner” in this presidential campaign — can get away with saying what he said about Fiorina, well then I’m going to worry greatly about those who keep standing behind someone such as that who seeks to become the head of state and government and commander in chief of the world’s greatest nation.

This individual disgraced the presidential campaign a long time ago.