CLEVELAND — The first Republican debate of the 2016 campaign for president opened with an absolute bang as billionaire businessman Donald Trump refused to pledge his loyalty to the GOP.
Over the course of the next two hours, the 10 leading candidates for the Republican nomination argued about issues that included immigration, taxes, health care, individual rights and foreign policy.
And there were plenty of personality conflicts, too.
Here are five takeaways from Thursday's debate.
TRUMP AT CENTER STAGE
Trump may be leading his fellow GOP presidential candidates in many of the national polls, but he was the only candidate on stage who refused — in the very first moment of the debate — to commit to running only as a Republican.
The reality TV star and real estate mogul said he would prefer to be the Republican Party's nominee, but he wouldn't promise to back any nominee other than himself. "I will not make the pledge at this time," he said.
His answer drew an angry rebuke from Kentucky Sen. Rand Paul: "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."
That was one of the few moments when one of the other nine candidates on stage directly engaged with Trump. The closest anyone came later in the debate may have been former Florida Gov. Jeb Bush, who offered up a gentle critique.
"Mr. Trump's language is divisive," Bush said. "We're not going to win by doing what Barack Obama and Hillary Clinton do every day — dividing the country."
READY TO RUMBLE: CHRISTIE VS. PAUL
There was no such gentleness between Paul and New Jersey Gov. Chris Christie, who have fought over government mass data collection in the past and traded perhaps the most pointed barbs of the night.
Christie said he'd attended funerals of victims of the Sept. 11 attacks and slammed Paul's efforts in the Senate to thwart renewal of government surveillance programs. "Listen, senator, you know, when you're sitting in a subcommittee, just blowing hot air about this, you can say things like that."
Paul shot back, "I don't trust President Obama with our records." He continued, invoking an infamous interaction between Christie and Obama during the 2012 campaign: "I know you gave President Obama a big hug, and if you want to give him a big hug again, you go right ahead."
HOME FIELD ADVANTAGE FOR KASICH
It was a solid night for Ohio Gov. John Kasich, who was the last candidate to make the cut for the debate as the 10th-ranked candidate in the average of national polls Fox News used to select the participants.
Kasich earned a rousing round of applause for his answer to a question about same-sex marriage. He said he opposes gay marriage, but when asked how he would explain that position to a child who announced he or she was gay or lesbian, he said: "I'm going to love my daughters no matter what they do. Because you know what? God gives me unconditional love, and I'm going to give it to my family and my friends and the people around me."
The former congressman, who attended a same-sex union shortly after a U.S. Supreme Court ruling made gay marriage legal nationwide, said that "issues like that are planted to divide us."
RUBIO AND WALKER COOL AND CALM
Avoiding the debate's testy back-and-forth were Florida Sen. Marco Rubio and Wisconsin Gov. Scott Walker, who mostly stuck to giving answers to the questions posed.
After an incendiary answer from Trump about his widely condemned comments about immigrants from Mexico, Rubio displayed his command of the issue by telling the crowed at Quicken Loans Arena that immigrants who live in the U.S. illegally are from Central American nations such as Guatemala and El Salvador, and are overstaying their legally obtained visas — as opposed to sneaking over the border.
Rubio also earned some of the loudest applause of the night when he offered up one of his well-used zingers to mock Clinton. "Well, first let me say, I think God has blessed us. He's blessed the Republican Party with some very good candidates," he said. "The Democrats can't even find one."
Walker, meanwhile, talked often of his record in Wisconsin. He said even when he drew over 100,000 protesters to the state Capitol, upset by his ultimately successful effort to strip away the union rights of most public employees, he was "trying to do the right thing" and acted in an upright manner.
He said he is "not a perfect man," but he has tried to act with respect.
"What God calls us to do is follow his will," he said. "And, ultimately, that's what I'm going to try to do. And I hope people have seen that in my state."
Amid all the fireworks, there was little to no chatter during the GOP debate about an issue which Republicans have obsessed for months: Clinton's use of a private email server while secretary of state and the deadly 2012 attacks on the U.S. consulate in Benghazi, Libya.
It was left to Walker to first mention Clinton's email habits when answering Russia's threat to U.S. allies in NATO, and that came with just 20 minutes left in the debate. Former Arkansas Gov. Mike Huckabee was first to mention the Benghazi attacks, during his answer to the next question — but it was only as an aside.
Bykowicz contributed to this report from Washington.
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