Analysis: Trump fends off debate mockery, trips on specifics. Will his supporters care?

His challengers should know by now that they can’t beat Donald Trump at mockery, although Florida Sen. Marco Rubio and Texas Sen. Ted Cruz tried anyway in Thursday’s two-hour presidential debate. For the second straight Republican debate, civility swiftly gave way to mayhem.

Within the first five minutes, rhetoric flared about 2012 nominee Mitt Romney’s unprecedented broadside earlier in the day against Trump, a belittling bit of innuendo about the size of Trump’s hands and, astonishingly, the first debate reference ever by a candidate about the dimensions of his male anatomy. (By Trump, predictably.)

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Were this a normal campaign, Trump would have lost the debate, Rubio would have damaged himself, and Ohio Gov. John Kasich would have won. Throughout, even when prodded by the moderators, Kasich refused to join in the back-seat rumble and kept the mien of a parent threatening to stop the car if the fisticuffs didn’t end.

But this campaign is as far from normal as any in modern history, and it remains both possible and probable that the debate changed nothing at all.

Thursday’s debate occurred as panic peaked among Republicans. Party leaders, along with the other candidates, had once thought that Trump would do himself in, and then that someone would rise as a singular challenger to finish him off. Neither has happened. Instead, powered by a growing swath of voters, Trump has won 10 of 15 Republican contests and is favored to extend that record on Saturday and Tuesday when ballots are cast in eight more states, the biggest of which is Michigan.

Part of the trouble for his challengers is that Trump ignores both the normal rules of candidate behavior and the laws of political gravity. No utterance has been enough to deep-six his campaign, though much of what he’s said since entering the race last June would have killed off anyone else.

His voters are responding not to his assertions but to his ability to give voice to their frustration. So they have not been particularly responsive to the kinds of attacks that dominated much of the debate. Rubio and Cruz both raised the issue of the Trump University real estate school, which is the focus of a lawsuit by former students.

As he was in the last debate, Rubio was the most assertive. The tone was set early when he criticized the fact that Trump’s clothing line is manufactured in Mexico.

“This little guy has lied so much—” Trump started to say.

“Here we go,” Rubio interrupted.

“—about my record,” Trump finished.

“Here we go; it’s personal,” Rubio interrupted again.

“He has lied so much about my record,” Trump said.

The two talked over each other, prompting questioner and Fox News host Chris Wallace to implore: “Sen. Rubio, why don’t you let him finish?”

Cruz treated Trump like an errant child — ironically, after calling Trump and Rubio “bickering schoolchildren.”

“Donald, please, I know it’s hard not to interrupt. But try,” Cruz said. “Breathe. Breathe. Breathe.”

“Lyin’ Ted,” Trump replied.

“You can do it. You can breathe. I know it’s hard. I know it’s hard,” Cruz countered.

If Trump gave as good as he got in those exchanges, he faltered during the debate’s calmer sections.

All three Fox questioners confronted Trump with facts that contradict some of his common promises. They asked how he would pay for a tax cut that could cost $10 trillion over 10 years, and pointed out that his proposed cuts came nowhere near that amount.

“Your numbers don’t add up, sir,” Wallace said after Trump tried to explain himself.

Fox News anchor Megyn Kelly aired video clips of Trump contradicting himself on support for the Afghan war, acceptance of Syrian refugees and his assertion weeks ago that President George W. Bush lied about weapons of mass destruction being found in Iraq. Trump variously claimed that he had misunderstood or had changed his mind after he studied the issues.

Questioner Bret Baier asked Trump about his vow in an earlier debate to sanction waterboarding and worse against Islamic terrorists, and to target their families as well.

“So what would you do, as commander-in-chief, if the U.S. military refused to carry out those orders?” Baier said.

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“They won’t refuse. They’re not going to refuse me. Believe me,” Trump replied.

“But they’re illegal,” Baier said of the tactics.

Rubio scalded Trump anew on his loose grasp of foreign policy, which Trump has often suggested he would handle with a tag team of strength and deal-making. (Trump gave him new ammunition by suggesting Thursday that “wouldn’t it be nice if actually we could get along with Russia, we could get along with foreign countries, instead of spending trillions and trillions of dollars?” His mild assessment of Russia runs counter to the views of most Republicans.)

“As we’ve seen throughout this campaign, Donald has not shown a seriousness about the issues of foreign policy,” Rubio said. “He just simply hasn’t.”

Trump didn’t defend himself, other than to declare, again, that Rubio “is not a leader. Believe me.”

The exchanges illustrated the hope of the other candidates that the normal rules might apply to Trump, that he would suffer both for his refusal to drill down on policy specifics and his reliance on bullying. At one point, Cruz opined that “the American people understand that yelling and cursing at people doesn’t make you a tough guy.”

In the Republican primaries so far, however, Trump has prevailed by doing just that. However he was targeted on Thursday night, it seemed a stretch to think that more than eight months into Trump’s ascent, his supporters might suddenly want something different.

cathleen.decker@latimes.com

For political news and analysis, follow me on Twitter: @cathleendecker . For more on politics, go to latimes.com/decker.

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