President Trump is masterful at his rallies. I’ve never seen anyone work a crowd better. Able to control the microphone, he’s loose, conversational, fluent, interesting, funny and even sometimes charming. He connects with people.

That’s not what he did September 29, however, during the first presidential debate. Many conservatives won’t like hearing this, but Trump underperformed while Joe Biden exceeded the very low expectations set for him. The ex-vice president simply had to show up and not exhibit dementia; the president had to impress. This he did not do. And he can — and must — up his game at the next debate, which also happens to be the last one.

I know, I’ve read the comments by conservatives claiming that Trump was impressive, that he won the contest. They cite certain polls supporting their position just as leftists trumpet polls indicating the opposite. I’m not here to claim that Trump won or lost or which polls are correct, however, because that’s the wrong way to view matters.

One thing you learn as a serious athlete, if you possess some wisdom, is the truth of the saying, “The only person worth feeling superior to is your former self.” If you chalk up a victory but perform terribly, you’ll be left unsatisfied.

At least, however, you do get the same W, and this is true whether you win by a nose or a mile. But with a debating politician, victory margin absolutely matters. Winning by a hair and capturing another, let’s say, one percent of “undecideds” is not as good as a resounding victory that sways another eight percent.

With everything arrayed against President Trump — from Big Tech bias to mainstream media malevolence to rampant vote fraud — he must seize every opportunity and run the table in public appearances. He cannot afford to leave arrows in his quiver.

One major issue is that Trump came off as angry Sept. 29, with his demeanor and frequent interruptions. Yeah, I know what some of you are thinking: “He has a right to be angry!” And with the bias against him, the continual unfair attacks and leftist witch hunts, yes, he does. But here’s the point:

You know why he’s angry. I know why he’s angry.

But the undecided voters largely have no idea.

If they did, they wouldn’t be undecided.

Remember, these people generally aren’t very conversant with the issues and may not pay much attention to politics until shortly before an election, when they may tune in to some news or a presidential debate. Now, put aside the projection — ascribing one’s mindset to others is a common failing — and consider things from their uninformed perspective.

“Why is this man so angry?” they may think. “He seems rude and not very nice.” Sure, it’s not fair. But life’s not fair.

Note here that in a debate, style supersedes substance. The participants make all sorts of claims, and undecided voters largely don’t know who’s telling the truth (again, they wouldn’t be undecided were it otherwise). Image matters most.

I think here of a man I spoke with years ago who didn’t like Barack Obama and his health plan, but who was enamored of Bill Clinton. When I pointed out that the latter was also a nationalized health care proponent, the man replied, “I know. But I like him.”

Yeah, I get it, it’s silly. But that man reflects a large swath of the electorate — and winning elections requires capturing a good portion of their votes.

The point is that many people make decisions, voting decisions in particular, on emotional bases. So you must reach them emotionally. As to this, note that a study years ago found that if a speaker says something well, he’ll sway people almost regardless of his message. Others have observed that the most charismatic candidate tends to win an election even if he has an inferior platform.

Regarding the difference between campaign-rally Trump and Sept. 29-debate Trump, coming to mind is an old interview with late, famed comedian Jackie Gleason. Explaining why he preferred live performances to making movies, he said that a comedian times his jokes based on the audience’s reactions. As to timing them on film sets where you don’t have this luxury, Gleason said, “I’ve never really seen anyone do it well.”

I believe a similar phenomenon explains Trump’s varying performances. At his rallies, the president enjoys huge partisan crowds that cheer and applaud enthusiastically. They not only help him time what he does, but, more significantly, he feeds off their positive energy and directs positive energy back. Note that the president enjoyed the same at the 2016 Republican debates, where there was a vociferous segment of Trump partisans.

Not only are general election debates different, but the September 29th affair was unprecedented: Thanks to COVID paranoia, the room was nearly empty with a small, distant, quiet audience of 80 or 90 people (I didn’t even know they were there). In this situation, your mentality can change: Instead of being influenced by and focusing largely on the audience, you will, if you react instinctively, be influenced by and focus on the only one(s) providing stimuli — your opponent(s).

In Trump’s case, this was Joe Biden with his prevarications and moderator Chris Wallace with his bias. They directed negative energy at the president — and he directed negative energy back.

(To be fair, he also came loaded for bear.)

In fact, Trump’s enemies can use his sensitivity to others’ comments and behavior against him by pushing the right buttons. He absolutely must not let this happen, and the next debate must not be a repeat performance of the first.

So here’s my message to President Trump: Don’t let Biden and the moderator goad you into grouchiness. Cultivate the campaign-rally Trump; if you have to, visualize your millions of supporters cheering and applauding in television-land. You can be aggressive, but do it with charm, wit and a twinkle in your eye. Kill them with cute cleverness.

Lastly, relating to emotion-grabbing substance, emphasize Democrat radicalism. Some undecideds will be decidedly shocked when reminded of plans to dismantle the police and ICE, for abortion up till birth, to put boys in girls’ bathrooms, for free healthcare for illegals, to end deportations even of criminals, for absorbing suburbs into cities, etc.

Oh, and don’t forget to mention Bidengate and to expose the moderator bias.

Mostly, though, remember that image is paramount. It doesn’t matter if the other guy’s the radical if you’re the man who, to the uninformed, seems like one.