Hillary Clinton will almost certainly win Monday night’s epic presidential debate on points — and still could lose.

It’s hard to see how Clinton, who has marinated in public policy for 30 years and is preparing for the debate like it is the invasion of Normandy, won’t best Donald Trump on substance.

Her strength in this area perfectly matches Trump’s weakness. Trump has appeared to learn for the first time in public such basic information as that the Trans-Pacific Partnership doesn’t include China and that Russia has already invaded Ukraine. He sometimes reads his speeches as if they include revelations to him — “so true,” he’ll interject after coming across a striking fact or observation in the text.

So Trump won’t be particularly well-informed, and figures it won’t particularly matter — and may be right.

Trump has a built-in advantage in that there is a lower standard for him — not because the media isn’t tough enough on him, as all the media mavens agree, but because he is the de facto challenger and candidate of change in a change election. Trump can win by clearing a bar of acceptability, whereas Clinton has to either clearly wound Trump or make a compellingly positive case for herself that has so far eluded her in both 2008 and 2016.

To be sure, Trump will be on treacherous terrain. He can’t bully and mock Clinton. Without a teleprompter, message discipline still tends to elude him. The one-on-one format for an hour and a half could make his thin knowledge painfully obvious. And any misstep or outburst that reinforces the idea that he lacks the qualities to be commander in chief would be devastating.

But Trump just needs to seem plausible, and the very fact that he is on a presidential-debate stage, the most rarified forum in American politics, will benefit him. During the Republican debates, the intangibles worked in his favor, and they presumably will on Monday, too. Trump is a big personality with a dominant physical presence. His critics often sneeringly say he is a reality-TV star, but you don’t become one without charisma and a performative ability that are major political assets.

Trump will have to stumble badly — and probably sabotage himself — to live down to Hillary’s critique of him. She has made her campaign almost entirely about how he is a monstrous madman. Trump doesn’t need to mount a convincing, detailed defense of his tax or child-care plan or anything else to invalidate Clinton’s critique of him; he just needs to seem a reasonable person.

That is why Trump shouldn’t be the aggressor. As long as he’s firm and calm, he is implicitly rebutting the case against him on temperament. Then he can look for a big moment or two that will be memorable and drive the post-debate conversation.

These contests aren’t evaluated by college-debate judges. Trump won one of the Republican primary debates with his barbed quip in response to Vicente Fox’s vulgar declaration that Mexico wouldn’t pay for the wall, “The wall just got 10 feet higher.” This wasn’t an argument or a policy; it was a sentiment. If Trump has taught us anything, it is that simple, evocative statements can make up for a multitude of evasions and confused nonanswers.

In the past, most presidential debates have had a slight or ephemeral effect on the race. Monday could be different because it is an event tailor-made for Trump to change one of the main factors holding him back. By roughly 60 percent to 30 percent, people think Clinton is prepared to be president; by roughly 60 percent to 30 percent, people think Trump is not. A credible performance could move that number for Trump, and appreciably increase his odds of winning the presidency.

Such is the dynamic of the race and the way most voters absorb information that Hillary Clinton could “win” on points, and still lose ground.

Rich Lowry can be reached via e-mail: comments.lowry@nationalreview.com.