Donald Trump finally met his match in a debate. Kamala Harris not only dominated and clobbered him, she goaded him into appearing unhinged.

It was arguably the best presidential debate performance since Ronald Reagan eviscerated President Carter in 1980 with his classic lines: “There you go again” and “Ask yourself, are you better off than you were four years ago?”

It’s conventional to say that debates don’t matter much in a race’s final outcome. But that’s bunk. There are many times when they have. And the Harris-Trump debate is potentially one.

Harris came across as a tough scrapper who could think on her feet and conceivably handle the rigors of the Oval Office. Moderate swing voters in battleground states may have gained some confidence in her because she projected strength. And she didn’t really sound like a San Francisco liberal.

In short, the debate may well have shown swayable voters that Harris is fit to be president — and the ranting, scowling Trump is unfit.

But it’s doubtful Trump will lose any hard-core supporters. He never does, no matter how outrageous his actions. And that has always intrigued me.

Look, he’s everything our mothers told us not to be: a bully, braggart, whiner, liar and name-caller. He showed most of these ugly traits during the debate. Plus, he’s a convicted felon.

Regardless of Trump’s character faults, this is a very tight race because his core voters are steadfastly loyal.

In deep blue California, Trump received 6 million votes in 2020 — more than in any other state, although he lost here by nearly 2 to 1.

He’ll lose California again on Nov. 5 but doesn’t seem to have hemorrhaged supporters despite shameless behavior.

A poll of likely voters last month by the UC Berkeley Institute of Governmental Studies showed Harris leading Trump by 59% to 34%. He hadn’t lost any support since February, but Harris was running 7 percentage points stronger than President Biden.

So, who are these dedicated Trump voters and what motivates them? How can they back someone with such unsavory character? I called around.

“Character is a declining issue in politics — and a non-issue for a lot of people,” said Republican strategist Rob Stutzman, a never-Trumper. “I think the Bill Clinton era had a lot to do with it.”

Clinton and Trump both cheated on their wives. Clinton even did it next to the Oval Office. But Clinton never acted uncivilly and called his opponents “crooked” and “stupid” as Trump does.

“Politics is a team sport,” Stutzman added. “Trump is on their team whether they like him or not.”

Actually, many Republican voters just hate Democratic politicians.

“Republicans hate the left and Trump embodies someone who will fight back against the left,” Stutzman said.

I asked Republican strategist Matt Rexroad about that hate.

“It’s 100 percent true,” he said. “Anyone could be on the ballot with an ‘R’ and [Republicans] would vote for them.”

“Trump’s a protest vote against the status quo,” Rexroad continued.

That’s particularly true of rural residents who tend to vote Republican.

“They feel disenfranchised,” Rexroad said. “People in the biggest cities aren’t listening to them. A lot of people in San Francisco couldn’t find Modoc County on a map if their life depended on it. They know Placer County because they drive through it on the way to Tahoe.

“People between Bakersfield and Fresno, they don’t like what’s going on in Sacramento and Washington. They feel they’ve been left behind.”

Former Republican strategist Ken Khachigian, who grew up on a Visalia walnut and grape farm, says Trump speaks to the proverbial “forgotten man.”

San Joaquin Valley farmers are particularly frustrated that after record Sierra snowpacks they received only half the water they requested from the federal and state governments, Khachigian says.

And valley folks are “unhappy about a lot of the handouts for illegal immigrants — free medical care and free other services,” he added.

In Trump, he said, “they see someone who’s willing to [speak up] about what’s going on … He’s seen as strength and vigor and intensity.”

I called Mark Baldassare, chief pollster for the nonpartisan Public Policy Institute of California. He delved into the innards of several PPIC polls in recent months.

“The negativity [of Trump voters] is one thing that struck me,” he said. “It’s all doom and gloom. This is a group that’s particularly sour about the way things are going in the country, the state and their own lives.”

Roughly 98% believe that California and America are headed “in the wrong direction.” Around 92% think the state and nation will have “bad times” economically in the next 12 months. And 64% say their families are worse off financially than a year ago.

Also, 87% feel immigrants “are a burden” on California.

On many issues, Trump supporters’ views are the direct opposite of Democrats.

Examples: 60% say addressing climate change is “not an important concern,” 63% favor more oil drilling off the California coast, 92% would rather have lower taxes and fewer services than higher taxes and more services, 89% favor protecting gun rights over controlling gun ownership and 71% approve of the Supreme Court’s Dobbs decision overturning national abortion rights.

“A sizable portion feel that government is the problem, not the solution,” Baldassare says. “They feel ignored. One way to get attention is to say, ‘I’m for Trump. Listen to me.’”

Hopefully we can all listen to a second Harris-Trump debate. Each candidate needs it in a tight race and so do voters.