Donald Trump and Ted Cruz at the Fox Business Network Republican presidential debate at the North Charleston Coliseum in North Charleston, South Carolina.AP Photo/Rainier Ehrhardt

NORTH CHARLESTON, South Carolina—Seventeen Republican presidential candidates began last year with hopes of becoming their party’s nominee. Thursday’s debate underscored that there are only four candidates left with a credible chance of winning: Ted Cruz, Donald Trump, Marco Rubio, and Chris Christie.

The tone of the Charleston debate was set by two heated showdowns at the outset: a birther brouhaha between Cruz and Trump, and a fight between Rubio and Christie over who’s a legitimate conservative. Cruz and Trump later clashed over the senator’s attack on Trump holding liberal “New York values.”   

Using his well-honed legal skills, Cruz ably turned the tables on Trump, citing the businessman’s declining numbers as a sign of desperation in raising questions about his eligibility to be president. But he faltered in backing up his talking point about Trump’s “New York values,” allowing Trump to score points in his rebuttal by invoking 9/11 and defending the heroism of New York City’s first responders. Despite starting on the defensive, Trump had his strongest debate of the campaign. His improved discipline and preparation demonstrated he is a front-runner with a clear shot at the nomination.

Rubio effectively put Christie on the defensive by reminding the audience that the New Jersey governor held more-liberal positions on gun control, Common Core, and abortion. He echoed the scathing attacks that his super PAC is currently airing against the New Jersey governor. Christie didn’t address the specifics, instead questioning Rubio’s motives and urging Republican unity. But Christie later underscored the importance of nominating a strong executive, mocking endless legislative debate and using a wonky exchange between Rubio and Cruz over a value-added tax (VAT) to go after both of them for engaging in an insular Senate argument.

These intraparty skirmishes will continue in the run-up to the Iowa caucuses and New Hampshire primaries, and their resolution will determine who are the final two Republicans standing. Cruz’s belated decision to hammer Trump suggests that only one of the antiestablishment candidates will emerge from February’s South Carolina primary with a clear shot at the nomination. And Rubio’s decision to focus on Christie underscores his campaign’s belief that he needs to consolidate establishment support once and for all. Iowa will help settle the grassroots favorite, while New Hampshire will crown the establishment leader.

All four candidates demonstrated one thing in common: an urgent tone that matched the pitched anger within the Republican electorate. Rubio, most significantly, amped up his anger in talking about ISIS, President Obama’s executive order on guns, and Hillary’s Clinton’s qualifications for higher office. Christie’s prosecutorial approach played well with the South Carolina crowd, particularly his jibes at Obama as a dictator and petulant child. Cruz is a natural performer who opened the debate by channeling deep anger among conservatives over Obama’s defense of Iran after the seizure of American military personnel. Trump was, well, Trump.  

Unfortunately for Jeb Bush, John Kasich, and Ben Carson, politics these days is more about performance than policy. Bush meekly reacted to Trump’s proposed travel ban on Muslims, saying, “I hope you’ll reconsider.” Carson answered his first question by talking process, thanking the moderators for asking him a question more quickly than in the past. Kasich sounded an optimistic, can-do note throughout his remarks, not offering the audience much red-meat rhetoric against Democrats. “We don’t need a weak person being president of the United States,” Trump said towards the debate’s end, capturing the GOP’s mood of the moment.

This debate concluded with an angry exchange over immigration between Rubio and Cruz, in which both candidates dumped their opposition research on each other. It could very well be a preview of the final showdown for the GOP nomination. Cruz holds a narrow lead in Iowa over Trump, while Rubio consistently leads the splintered establishment lane. Both improved their positions with feisty debate performances on Thursday night. It will be an ugly fight to the finish.

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