CLEVELAND — The real question heading into Thursday’s primetime showdown here was whether the first debate of the Republican presidential candidates would turn into the Donald Trump show. Seconds in, the answer was obvious.

“Is there anyone on stage, and can I see hands, who is unwilling tonight to pledge your support to the eventual nominee of the Republican party and pledge to not run an independent campaign against that person,” moderator Bret Baier of Fox News told the 10 Republicans on stage.

“Again, we’re looking for you to raise your hand now,” Baier explained. “Raise your hand now if you won’t make that pledge tonight.”

One hand goes up. And the crowd starts boo-ing.

“Mr. Trump,” Baier said in response, as the crowd inside the Quicken Loans arena roars.

“Mr. Trump to be clear, you’re standing on a Republican primary debate stage,” Baier said. “The place where the RNC will give the nominee the nod.”

“I fully understand,” Trump said. (VIDEO: Trump Delivers Instant Chaos At Start Of Primetime Debate)

Baier, continuing, said: “And that experts say an independent run would almost certainly hand the race over to Democrats and likely another Clinton. You can’t say tonight that you can make that pledge?”

“I cannot say,” Trump said, though adding: “If I’m the nominee, I will pledge I will not run as an independent…I want to win as the Republican. I want to run as the Republican nominee.”

Rand Paul, unprovoked, jumped in for an attack: “Hey, look, look. He’s already hedging his bet on the Clintons, OK? So if he doesn’t run as a Republican, maybe he supports Clinton, or maybe he runs as an independent…but I’d say that he’s already hedging his bets because he’s used to buying politicians.”

For the rest of the debate, the other nine candidates were pressed by Baier, Megyn Kelly and Chris Wallace on the issues they were most vulnerable on, but Trump continued to capture attention throughout the night. (VIDEO: Trump Turns Tables On Megyn Kelly: ‘If You Don’t Like It, Then I’m Sorry’)

Pressed On Vulnerabilities

Neurosurgeon Ben Carson was asked to defend his inexperience in the public arena, with Kelly referencing mistakes made while on the campaign trail.

“Experience,” Carson replied, “comes from a large number of different arenas, and America became a great nation early on not because it was flooded with politicians, but because it was flooded with people who understood the value of personal responsibility, hard work, creativity, innovation, and that’s what will get us on the right track now, as well.”

Likewise, Florida Sen. Marco Rubio was questioned on his lack of executive experience.

“It’s important to be qualified,” Rubio said, “but if this election is a resume competition, then Hillary Clinton’s gonna be the next president, because she’s been in office and in government longer than anybody else running here tonight.” (VIDEO: Rubio: If This Election Is Based On Resume, Hillary Will Win)

Texas Sen. Ted Cruz was asked how he can “win in 2016 when you’re such a divisive figure.”

“I believe the American people are looking for someone to speak the truth,” Cruz replied. “If you’re looking for someone to go to Washington, to go along to get along, to get — to agree with the career politicians in both parties who get in bed with the lobbyists and special interests, then I ain’t your guy.”

Ohio Gov. John Kasich, who enjoyed the home-field advantage of a boisterous crowd, was questioned on his support for Medicaid expansion, something conservatives have protested.

“You should know that President Reagan expanded Medicaid three or four times,” Kasich said.

Wallace asked former Florida Gov. Jeb Bush about his infamous comment calling illegal immigration “an act of love.”

“I believe that the great majority of people coming here illegally have no other option,” Bush said. “They want to provide for their family. But we need to control our border.”

When Wisconsin Gov. Scott Walker was asked about his past support for comprehensive immigration reform and how his views have changed on the issue, Walker explained that he “actually listened to the American people.”

“And I think people across America want a leader who’s actually going to listen to them,” he said. “I talked to border state governors and other elected officials. I look at how this president, particularly through last November, messed up the immigration system in this country. Most importantly, I listened to the people of America.” (VIDEO: Walker On His Foreign Policy: ‘You’ll Find Steel’)

Former Arkansas Gov. Mike Huckabee was questioned on whether his views on issues like abortion could make it hard to attract independents in a general election.

Talking about abortion, Huckabee said: “A lot of people are talking about defunding Planned Parenthood, as if that’s a huge game changer. I think it’s time to do something even more bold. I think the next president ought to invoke the Fifth, and Fourteenth Amendments to the constitution now that we clearly know that that baby inside the mother’s womb is a person at the moment of conception.” (VIDEO: Huckabee: The Military Is Not A Social Experiment)

One of the most tense moments of the night came when New Jersey Gov. Chris Christie and Paul battled after the governor said he stood by his past comments saying he would blame Paul for a terrorist attack because of his opposition to bulk collection phone records.

“I don’t trust President Obama with our records,” Paul said. “I know you gave him a big hug, and if you want to give him a big hug again, go right ahead.”

“You know, Sen. Paul?” Christie said. “Senator Paul, you know, the hugs that I remember are the hugs that I gave to the families who lost their people on September 11th…those had nothing to do with politics, unlike what you’re doing by cutting speeches on the floor of the Senate, then putting them on the Internet within half an hour to raise money for your campaign.” (VIDEO: Rand, Christie Trade Vicious Barbs Over Civil Liberties)

Kelly, who Trump did not hide his distaste for, rattled off a list of nasty things he has said about women over the years.

“Mr. Trump, one of the things people love about you is you speak your mind and you don’t use a politician’s filter,” Kelly said. “However, that is not without its downsides, in particular, when it comes to women. You’ve called women you don’t like “fat pigs, dogs, slobs, and disgusting animals.”

“Only Rosie O’Donnell,” Trump said to laughter. (RELATED: Trump: The Questions To Me Were Not Nice)

“Honestly, Megyn, if you don’t like it, I’m sorry,” Trump said. “I’ve been very nice to you, although I could probably maybe not be, based on the way you have treated me.”

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