Brian Snyder / Reuters

CLEVELAND, Ohio—It is Donald Trump’s world, and the rest of the Republican candidates are just living in it. That much was abundantly clear as the candidates met for their first debate on Thursday.

When it was the other candidates’ turn to speak, they did what politicians do—they recited talking points, they speechified, they explained. Trump performed. He gloated, he insulted, he chewed up the stage. It was shocking. It was crazy. It was astonishingly good television.

The night began with a bang when, asked if any of them would decline to pledge to support the eventual Republican nominee, only Trump raised his hand. The stunned moderator, Fox News’s Bret Baier, tried to explain the stakes—that an independent candidacy would likely split the GOP and hand the election to the Democrats. Trump said he understood. “I have to respect the person,” he said, adding, “If I’m the nominee, I will pledge I will not run as an independent.”

The restive crowd that had packed the Cleveland Cavaliers’ arena booed.

The press had made a pre-debate parlor game of trying to figure which of the other candidates would make a run at Trump—a tricky business given the tycoon’s imperviousness to criticism and penchant for personal insults. In the event, it was Rand Paul, the Kentucky senator, who went for it, saying Trump was “hedging his bets because he’s used to buying politicians.” Trump shrugged it off.

When another moderator, Megyn Kelly, recited a list of the insults Trump has directed at women, he quipped, “Only Rosie O’Donnell.” He chalked the remarks up to political correctness: “We have a good time. What I say is what I say,” he said with his trademark smirk. “And honestly, Megyn, if you don’t like it, I’m sorry.”

Trump proceeded in this vein, combining outrageousness with evasiveness, for the rest of the night. He refused to substantiate his immigration claims; he praised single-payer health care; he said his views on abortion had “evolved.” He didn’t seem to be doing himself any favors, but who can really say? His candidacy has already gleefully broken every supposed rule of politics; any further predictions about his campaign seem destined for the punditry scrap-heap.

Over on planet Earth, between Trump eruptions, the other candidates were having a different, more serious and, let’s be honest, more boring debate. The prevailing strategy was to try to win this real-world debate rather than try to play on Trump’s terms. Jeb Bush, the but-for-Trump frontrunner, did not distinguish himself. Pressed to explain his views on immigration, the Iraq war, and education, he seemed always to be dancing on the cliff’s edge of incoherence.

Marco Rubio, the Florida senator, was polished and charismatic, emphasizing his youth—“This election better be about the future, not the past”—and his humble, “paycheck to paycheck” roots. But he seemed evasive on a question about abortion, saying he had “never advocated” for exemptions for rape and incest. Scott Walker, the Wisconsin governor and Iowa favorite, positioned himself as the sensible one—“I’m a guy with a wife, two kids, and a Harley”—and had a good moment when he interrupted the moderators to turn the foreign-policy discussion back to the Democratic frontrunner: “Everywhere in the world that Hillary Clinton touched is more messed up today than before” her tenure as secretary of state.

Paul, who seemed always to be yelling, got into a heated spat over civil liberties with Chris Christie, the New Jersey governor. Christie also tussled with Mike Huckabee, the former Arkansas governor, over entitlements like Social Security, which Christie wants to reform and Huckabee wants to preserve. I mention these names here partly to remind you that these men are also running; in a 10-way debate, those who didn’t stand out mostly faded from view. Even Christie’s legendary pugnaciousness seemed to have lost its novelty. Ted Cruz, the Texas senator, and Ben Carson, the neurosurgeon, were also mostly in this category: When they spoke, they were fine, and then you forgot they were there until it was their turn again.

The night’s surprise standout was Ohio Governor John Kasich, who had the advantage of a hometown crowd that ardently cheered his every answer. (The other sitting governors in the race—Walker, Christie, and Louisiana Governor Bobby Jindal, who did not poll well enough to qualify for the main debate—do not enjoy Kasich’s popularity in their home states.) Standing in 10th place, Kasich, who launched his campaign just a few weeks ago, barely made it onto the stage.

Perhaps because he had almost nowhere to go but up, Kasich impressed many observers with his sincerity. He defended his expansion of Medicaid as a money-saving measure; he refused to engage with a question about Trump. Most notably, he said that while he held an “old-fashioned” view about gay marriage, he had recently been to a friend’s gay wedding and would love and accept his daughters if they were gay.

Kasich repeatedly articulated an inclusive vision for the GOP—a vision starkly different than Trump’s Mexican-bashing, screw-the-losers mentality. It’s clear that a large swath of the GOP is responding to Trump’s call, but on Thursday, another segment seemed to be responding to Kasich’s. It’s anybody’s guess whose party this is. It will take the next few months of fighting to find out.

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