Jeb Bush speaks during the CNBC Republican Presidential Debate in Boulder, Colo. (Justin Sullivan/Getty Images)

Jeb Bush deserves headlines from Wednesday’s anarchic GOP debate, but not the good kind. Something like: “Is Bush Finished?”

The evening in Boulder, Colo., will be remembered for interruptions, non sequiturs, mangled facts and general chaos. But the most significant impact may have been to dramatically lengthen the odds that Bush, the dutiful scion, will follow his father and brother into the White House.

The key moment came fairly early in the debate when Sen. Marco Rubio (Fla.) — considered Bush’s biggest rival for consolidating the support of the GOP establishment — was asked about having missed so many Senate votes while out on the campaign trail. Rubio responded by attacking “the bias that exists in the American media today,” claiming there is a double standard and that Republicans are judged more harshly than Democrats.

Bush sallied forth. “I’m a constituent of the senator,” he said, “and I helped him and I expected that he would do constituent service, which means that he shows up to work.” In his characteristic look-here-old-boy sort of way, Bush told Rubio he should either perform his duties or “just resign and let someone else take the job.”

Rubio shot back that Bush never complained about all the votes missed in 2008 by Sen. John McCain (Ariz.), to whose campaign Bush has compared his own. Then Rubio gave his one-time mentor the back of his hand: “The only reason why you’re doing it now is because we’re running for the same position, and someone has convinced you that attacking me is going to help you.”

The crowd cheered. Bush made no retort. Rubio had made him appear, in Winston Churchill’s memorable phrase, “a sheep in sheep’s clothing.”

Bush had spent the past week trying to assure donors and supporters that he had the drive, desire and political skill to fight with no holds barred for the nomination. Wednesday’s performance was woefully unconvincing.

Rubio, by contrast, had his best outing thus far. He was sharp and aggressive throughout, deflecting any question he didn’t want to answer with a fresh round of media-bashing.

If I were a would-be Republican kingmaker of the establishment persuasion, I’d invite Rubio for lunch — and remind Bush of his recent declaration that there are “really cool things I could do other than sit around, be miserable, listening to people demonize me and me feeling compelled to demonize them.”

Sen. Ted Cruz (Tex.) was at the top of his game, showing he can be more clever and eloquent than Rubio in attacking perceived — or imagined — media bias. “This is not a cage match,” he pronounced. “And, you look at the questions — ‘Donald Trump, are you a comic-book villain?’ ‘Ben Carson, can you do math?’ ‘John Kasich, will you insult two people over here?’ ‘Marco Rubio, why don’t you resign?’ ‘Jeb Bush, why have your numbers fallen?’ How about talking about the substantive issues the people care about?”

That peroration drew one of the night’s biggest ovations. But it came in response to a question about Cruz’s position on the budget deal between President Obama and outgoing House Speaker John A. Boehner (R-Ohio). Somehow, that didn’t fit Cruz’s definition of substance?

The battle among Rubio, Cruz and Bush was amusing, but it was for primacy among also-rans. The two leaders — billionaire Donald Trump and Ben Carson — went unscathed, generally managing to stay out of the fray.

Republican presidential candidates sparred over experience, took jabs at their Democratic opponents and even shared a few laughs during CNBC's main debate in Boulder, Colo. (Sarah Parnass/The Washington Post)

Not that Ohio Gov. John Kasich didn’t try to make their lack of experience an issue. Kasich opened the debate with a screed: “My great concern is that we are on the verge, perhaps, of picking someone who cannot do this job.” He went on to mention Carson’s proposal to replace Medicare and Trump’s vow to deport 11 million undocumented immigrants as examples of “fantasy.”

But nobody wanted to join Kasich in ganging up on the improbable front-runners. New Jersey Gov. Chris Christie was eager to get in on the blame-the-media action that seemed to be working so well for the others. Former Arkansas governor Mike Huckabee seemed to want to show that he has found his missing sense of humor. Businesswoman Carly Fiorina pushed “play” on a recording of her previous debate performances. Sen. Rand Paul (Ky.) was present.

Trump was brassy, Carson was serene. Neither said or did anything to dissuade their legions of followers. When pressed on glaring contradictions, they simply denied saying or proposing things they said and proposed. All the politicians are still playing second fiddle to a real estate mogul and a retired neurosurgeon who somehow have stolen the Republican Party.

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