GOP debate: Trump, Bush, Cruz, Paul, and Rubio mix it up

The first primetime Republican primary debate of the 2016 election cycle was not, as many were predicting, all about Donald Trump.

"We don't want to make it the Donald Trump show," said Fox News' Chris Wallace, one of the moderators, on Tuesday. "But it is."

The billionaire businessman has lit up the early GOP primary with his trash-talking approach to politics, and he certainly didn't pull any punches during Thursday's debate, which was hosted in Cleveland, Ohio by Fox News.

He tossed some barbs at other candidates, at President Obama, even at Rosie O'Donnell - and he received a few in return. But his combative style didn't dominate the evening. Instead, most of the other candidates focused on burnishing their own strengths and carving out their own brands within a winnowed-but-still-crowded lineup.

Former Florida Gov. Jeb Bush positioned himself as a sober problem-solver, vowing not to use "wedge issues" like immigration and education to score cheap political points. Texas Sen. Ted Cruz did not relent in his war on the GOP establishment, reminding voters about his scuffles with Republican Senate leaders who "don't honor their commitments."

Florida Sen. Marco Rubio promised to be the voice of the new generation and warned his party that Hillary Clinton will win the election if the campaign is boiled down to a "resume competition." Kentucky Sen. Rand Paul reminded the audience of his fight against government surveillance, drawing fierce pushback from New Jersey Gov. Chris Christie, who recalled his personal exposure to the September 11 terror attacks. Ohio Gov. John Kasich played to the hometown crowd with an enthusiastic performance that was suffused with references to his faith.

Of course, not everyone stood out. Some performances were lackluster, but none of the candidates committed a gaffe of campaign-ending proportions. This likely ensures that the full field will continue to soldier on through at least the next debate, which will take place Sept. 16 at the Ronald Reagan Presidential Library in California.

Here's a look at each candidate's performance - their most memorable lines, their potential weak spots, and whether they helped their cause or will have to hope for better luck next time.

Donald Trump

If the other candidates hoped Trump might rein in his bombast during Thursday night's primary debate, they were disappointed. The billionaire businessman lived up to his reputation as a provocateur, standing by several recent comments that have earned widespread condemnation.

On the very first question of the debate, Trump stood alone in refusing to pledge to support the eventual Republican nominee. He kept the door open to a third-party run in the general election, a move that would increase the chance that the Democratic nominee would win the election. The audience booed, and Rand Paul attacked him for it, accusing him of "hedging" his bets with the Clintons, since Hillary Clinton would likely be the beneficiary.

Who is presidential candidate Donald Trump?

Trump justified several offensive statements about women by claiming they were directed "only" at Rosie O'Donnell, with whom he once famously feuded. He repeated his claim that the Mexican government is actively sending its most undesirable citizens to the United States. He ridiculed several opponents, telling Kentucky Sen. Rand Paul during one verbal scuffle, "You're having a hard time tonight." And he framed his lack of political correctness as an asset, not a liability, declaring, "What I say is what I say."

If Trump's campaign has any discernible organizing principle, "What I say is what I say" might be it.

He didn't emerge unscathed, however, taking flak from several rivals onstage for having changed his positions on issues from health care reform to abortion. At one point, he even conceded, "I've evolved on many issues over the years," but he suggested former President Reagan had once done the same. He explained away his past flirtations with Democrats by pointing out the strongly-Democratic tilt of his home city of New York. In one particularly awkward exchange, he tried to justify his corporate bankruptcy filings by saying he was only taking advantage of U.S. laws to benefit his business interests.

It was a pugnacious performance - vintage Trump. He had more than a few strong lines, but he may have also sown doubts among Republican voters about his commitment to the conservative cause.

In a post-debate focus group for Fox News, several voters who started the night as Trump supporters told GOP pollster (and CBS News contributor) Frank Luntz that they'd thrown their support to other candidates, including Cruz and Arkansas Gov. Mike Huckabee.

Jeb Bush

Former Florida Gov. Jeb Bush had perhaps the most to prove coming into Thursday's debate, as the favorite of the GOP establishment who's seeking to court the party's skeptical base. In the end, he didn't crash and burn, but he wasn't the most dynamic debater onstage, either.

Who is presidential candidate Jeb Bush?

He began a bit unsteadily, offering somewhat halting answers to questions and occasionally stuttering. But after the first few questions, he offered clean, concise answers on three topics - Iraq, immigration, and education - that are seen as problem spots for his campaign.

On Iraq, he clearly stated the decision to invade in 2003, knowing what we know now, was a "mistake," but he suggested the Americans who gave their lives in the war did not die in vain. On education, he defended his support for Common Core state education standards but offered an olive branch to conservatives who disagree, but suggested states should be able to opt out of the state standards initiative without being federally penalized. And, he said they should maintain high standards nonetheless. On immigration, he stressed the need to secure the border but did not elaborate at length.

Bush also benefitted from being able to lean on his record as governor of Florida, citing conservative accomplishments from tax cuts to anti-abortion measures that could help him woo grassroots voters who have looked askance at his candidacy thus far.

Scott Walker

Wisconsin Gov. Scott Walker delivered a steady performance, but he seemed at times to fade into the background, even describing himself at one point as "aggressively normal."

Who is candidate Scott Walker?

He did not cite his fight against public employee unions in Wisconsin - and the resultant recall election that made him a national conservative hero - until his closing statement, losing a potential opportunity to remind GOP base voters why he earned their goodwill in the first place.

He did manage to speak with some fluency on foreign policy issues, however, which could quiet doubts among some Republicans about whether he has the policy chops to take on Hillary Clinton in the general election. He advocated a muscular defense posture, pledging to reinstate missile defense in eastern Europe and place NATO troops in Poland and the Baltic states to deter Russian aggression. And he snuck in one of the better zingers of the evening, tying recent cyberattacks on U.S. government systems and Hillary Clinton's email controversy into a single quip.

"The Russian and Chinese governments know more about Hillary Clinton's email server than do the members of the United States Congress," he said, eliciting laughter and applause from the audience.

Mike Huckabee

Former Arkansas Gov. Huckabee is a polished public speaker, and it showed during Thursday's debate, as he delivered a punchy, strongly conservative performance that highlighted his reputation as a culture warrior.

Who is presidential candidate Mike Huckabee?

He suggested the next president "ought to invoke the 5th and 14th amendments to the Constitution" to offer due process and equal protection rights to fetuses, a move that could have far-reaching legal and political consequences. He decried moves to allow gay and transgender people to serve in the military, declaring, "The military is not a social experiment. The purpose of the military is to kill people and break things."

He was ready with a sound byte on the Iranian nuclear deal, citing past Iranian threats against the U.S. and saying, "When someone points a gun at your head and loads it, by God, you ought to take them seriously."

And in perhaps the most eyebrow raising moment of the night, he pitched his proposal for a "Fair Tax" which would tax consumption rather than earnings and hit everybody, "Including illegals, prostitutes, pimps, drug dealers, all the people that are freeloading off the system now."

Ben Carson

Retired neurosurgeon Ben Carson has flaunted his lack of political experience as a positive attribute, but his subdued performance on Thursday demonstrated that he could probably use a bit more practice with the cut and thrust of presidential politics.

Who is presidential candidate Ben Carson?

He was often vague when he was pressed on specific proposals, offering esoteric prescriptions in place of policy detail. He suggested the most important attribute in a commander in chief is "having a brain" and the ability to "learn things rapidly" when he was asked why he believes he's prepared for the presidency. He suggested we should "utilize the tremendous intellect of the military" if we want to win wars against America's enemies, and he said his strategy to attract voters to the conservative cause is to "educate people."

At one point, he tried to differentiate himself from his competitors by pointing out his illustrious professional history as a physician. "I'm the only one to separate Siamese twins," he said.

But it wasn't enough to set Carson apart from the crowd, and he seemed to feel left out at times. When Fox News' Megyn Kelly gave Carson his second question of the night, he carped, "I wasn't sure I was going to get to talk again."

Ted Cruz

Texas Sen. Ted Cruz knows his place in the GOP field - he's the candidate who won't shy away from a fight with the Republican establishment, determined to deny his rivals any chance to outdo him among the conservative grassroots.

"If you're looking for someone to go to Washington to go along to get along, 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," he declared at the outset.

Who is presidential candidate Ted Cruz?

He stood proudly behind his recent fight with Senate GOP leaders, one of whom he termed a "liar" during a dispute over the Export-Import Bank, saying Republicans have helped build the U.S. federal debt because "we don't have leaders that honor their commitments."

He portrayed the other candidates as squishy on immigration, arguing, "A majority of the candidates on this stage have supported amnesty. I have never supported amnesty."

He outlined a deeply conservative agenda for his first day as president, vowing to rescind Mr. Obama's executive orders, defund Planned Parenthood, annul the Iranian nuclear deal, and move the U.S. embassy in Israel from Tel Aviv to Jerusalem.

"We see lots of campaign conservatives," he said. "But if we're going to win in 2016, we need a consistent conservative."

Marco Rubio

Florida Sen. Marco Rubio is seen as one of the GOP's best communicators, and he proved Thursday that reputation is well-deserved. He delivered perhaps the most crisp performance of the bunch, executing his lines cleanly and quickly, demonstrating a fluent grasp of a broad range of policy arenas, and delivering a few of the night's most memorable lines.

Who is presidential candidate Marco Rubio?

His message was relentlessly forward-looking. He warned his party that if the campaign is about the past, rather than the future - a "resume competition," as he called it - then Hillary Clinton will win the White House.

"If I'm our nominee, how is Hillary Clinton gonna lecture me about living paycheck to paycheck? I was raised paycheck to paycheck," he said during his first response. "How is she gonna lecture me about student loans? I owed over $100,000 just four years ago. If I'm our nominee, the election will be about the future."

And in what may have been the best zinger of the night, he dismissed Clinton and praised his fellow GOP candidates in one fell swoop: " I think God has blessed us. He's blessed the Republican Party with some very good candidates. The Democrats can't even find one."

Rand Paul

Kentucky Sen. Rand Paul was the quickest candidate to go on the attack Thursday. He told "CBS This Morning" he intended to "mix it up" in the debate Thursday, and he did just that, tearing into Donald Trump before he was even invited to speak, saying the billionaire "buys and sells politicians of all stripes."

He strove to reinforce his reputation for going against the grain, beginning and ending his closing statement by declaring, "I'm a different kind of Republican." And he while he distinguished himself from the other contenders on issues from health care to national security and government surveillance, he did so mostly by feuding with other participants onstage. Whether his in-your-face approach will pay dividends remains to be seen.

Who is presidential candidate Rand Paul?

He criticized Trump on several fronts, reserving particular scorn for Trump's prior support for a progressive health care reform proposal known as single-payer.

"News flash, the Republican Party's been fighting against a single-payer system...for a decade," Paul said. "So I think you're on the wrong side of this if you're still arguing for a single-payer system."

The most combative exchange of the night came after New Jersey Gov. Chris Christie criticized Paul's opposition to the government's post-9/11 surveillance programs. The senator immediately fired back, telling Christie, "You fundamentally misunderstand the Bill of Rights."

And for good measure, he reminded voters of Christie's embrace of President Obama in the aftermath of Hurricane Sandy in 2012, telling the New Jersey governor, "I don't trust President Obama with our records. I know you gave him a big hug, and if you want to give him a big hug again, go right ahead."

Chris Christie

Chris Christie has done hundreds of town halls during his time as New Jersey governor, as well as on the campaign trail, and that practice paid off in a punchy, polished performance.

Asked about some declining economic indicators in New Jersey, Christie shrugged it off, saying, "If you think it's bad now, you should have seen it when I got there." He then launched into an itemized list of economic accomplishments.

Who is presidential candidate Chris Christie?

He denounced Paul's opposition to government surveillance as nothing more than opportunistic political theater, telling the senator, "Listen, senator, you know, when you're sitting in a subcommittee, just blowing hot air about this, you can say things like that...When you're responsible for protecting the lives of the American people, then what you need to do is to make sure... that you use the system the way it's supposed to work."

Christie's performance may test whether the memory of September 11 still stirs as much passion among the Republican electorate as it once did. He took pains to remind the audience of his own personal exposure to the attacks and suggested the memory of that day has informed his hawkish approach to security policy.

"I was appointed U.S. attorney by President Bush on September 10th, 2001, and the world changed enormously the next day, and that happened in my state," he said. "This is not theoretical to me. I went to the funerals. We lost friends of ours in the Trade Center that day. My own wife was two blocks from the Trade Center that day, at her office, having gone through it that morning. When you actually have to be responsible for doing this, you can do it, and we did it, for seven years in my office, respecting civil liberties and protecting the homeland. And I will make no apologies, ever, for protecting the lives and the safety of the American people."

John Kasich

Ohio Gov. John Kasich was the final qualifier for the primetime debate on Thursday, enjoying a last-minute polling surge to narrowly land himself in the top ten. But with an energetic, optimistic performance - buoyed by an enthusiastically supportive home state crowd - he proved his conservative mettle while still nurturing his brand as a "big-tent" Republican who's willing to part with his party at times.

Who is presidential candidate John Kasich?

Kasich relied on his Christian faith to explain his occasional departures from GOP orthodoxy. He justified his decision to expand Medicaid under Obamacare by pointing out the good it's done in the lives of thousands of Ohioans. "We brought a program in here to make sure that people could get on their feet," he explained, "and do you know what? Everybody has a right to their God-given purpose."

He also disclosed that he'd recently attended the wedding of a gay friend, striking an inclusive tone on the divisive social issue while still emphasizing his own faith.

"Because somebody doesn't think the way I do, doesn't mean that I can't care about them or can't love them. So if one of my daughters happened to be that, of course I would love them and I would accept them. Because you know what? That's what we're taught when we have strong faith," he said. " God gives me unconditional love. I'm going to give it to my family and my friends and the people around me."