THE gloves came off in the sixth Republican primary debate, held in North Charleston, South Carolina, on January 14th, especially during exchanges between Donald Trump and Ted Cruz, the two front-runners, who until recently had enjoyed an unofficial alliance. “I recognise that Donald is dismayed that his poll numbers are falling in Iowa,” said Mr Cruz, in answer to a question about whether he might not qualify for the presidency because he was born in Canada, which, he said, was first raised by Mr Trump. An angry-looking Mr Trump retorted that Mr Cruz was “misrepresenting” how well he was doing. “I was all for you until you started that,” he said. The exchange escalated when Mr Cruz suggested that, by Mr Trump’s standards, he himself might not be eligible to run for the presidency; his mother was born in Scotland. (“But I was born here—big difference,” was Mr Trump’s reply). It then turned almost comedic when the pair (sort of) offered each other the vice-presidency: Mr Trump said he would choose Mr Cruz as vice-president…but that the cloud of contestable nationality hanging over his head was a problem. Mr Cruz said he would give Mr Trump the vice-presidency…so that he could take over the job if ever President Cruz were to be disqualified by a lawsuit challenging his eligibility. Mr Trump waved aside the offer. “I think I will go back to building buildings if it does not work out,” he said.

Their compellingly watchable exchange, which sidelined the other five candidates on stage, was ended by Marco Rubio, who said that he “hated to interrupt courtroom TV” and then tried to refocus the debate on attacks against President Barack Obama’s record. The youthful, first-term senator from Florida seemed Pavlovian for most of the evening, using much of his air time to go after Mr Obama with tirades that seemed rehearsed. Although Mr Obama has never made such a proposal, Mr Rubio claimed that he was convinced that if the current president could confiscate every gun in America and get rid of the Second Amendment, he would. He went on to say that the president’s recent push for tighter gun-control laws would not have prevented mass shootings because criminals don’t buy their guns at gun shows, but steal them or get them on the black market.

Jeb Bush had possibly his best debate so far, but it’s probably too late to salvage his ailing campaign. The former governor of Florida came across as reasonable and conciliatory most of the time. He dismissed Mr Trump’s wacky idea of temporarily banning all Muslims from entering America, pointing out that America needs allies such as Turkey, a Muslim country, in the fight against Islamic State. He paid a compliment to Nikki Haley, the Republican governor of South Carolina, who was sitting in the audience, for how she handled the aftermath of the horrific mass shooting at a black church in Charleston by a young white man—even though she had criticised him for his support of the Common Core, a set of academic standards, in her response to the president’s state-of-the-union address on January 12th. He even smiled graciously when Mr Trump insulted him by saying that “we don’t need a weak person being president of the United States, okay. Because that’s what we get if it were Jeb.”

Ben Carson, the retired neurosurgeon whose campaign recently seemed to implode as his staffers left in droves, made a joke about his own sleepy manner, but wasn’t much perkier during the debate. He evaded answering a question about whether Bill Clinton’s indiscretions were a legitimate topic and a (rather odd) follow-up question about whether Hillary Clinton was “an enabler of sexual misconduct”, by talking about American’s Judeo-Christian roots and railing against secular progressives. At another point in the debate he proposed solving the problem of Syrian refugees by sending them all to the Hasakah province, a mostly Kurdish part of the country, which would be a “perfect place” for them.

When Mr Rubio wasn’t attacking Mr Obama, he was sparring with Chris Christie, the governor of New Jersey, or with Mr Cruz. He claimed to like Mr Christie, but said the country cannot afford to have a president who supports the Common Core and gun control, backed the appointment of Sonia Sotomayor to the Supreme Court and made a donation to Planned Parenthood, a non-profit organisation providing reproductive health services: in short, a president who backed much of Mr Obama’s agenda. Mr Christie retorted that Mr Rubio was only attacking him because someone had whispered in his ear that it was a helpful strategy. He denied backing Ms Sotomayor or writing a cheque for Planned Parenthood.

The exchange between Mr Rubio and Mr Cruz was even testier. After Mr Cruz accused his colleague in the Senate of being soft on immigration, Mr Rubio attacked Mr Cruz for flip-flopping repeatedly on immigration, faulting him for changing his mind on doubling the number of green cards for legal immigrants, as well as for his support of cutting the defence budget. “That is not consistent conservatism,” Mr Rubio said of Mr Cruz’s record. “That is political calculation.”

John Kasich, the governor of Ohio, was the least colourful of the seven debaters, but he avoided the bad-tempered outbursts that marred his performance at a previous debate in Milwaukee. As usual, he touted his experience and his economic record in Ohio. He explained his plan to lower taxes, cut red tape and balance the budget. And he talked about his hopes of reviving the American dream, which had propelled him, the son of a postman, to the governorship of one of America’s most important states.

At this stage either Mr Trump or Mr Cruz probably has the best chance of winning the nomination. This is anathema to moderate Republicans. But unless Mr Bush makes a miraculous recovery or Mr Rubio graduates to become the establishment candidate, they may have to come to terms with having either a yellow-haired populist or a Mephistophelian demagogue (whose views are the lite-version of the populist’s) as their candidate. The Democrats’ camp must be rubbing their hands at the prospect.