Donald Trump and Sen. Ted Cruz talk over one another during a Republican presidential debate sponsored by Fox News at the Fox Theatre in Detroit.(Paul Sancya / Associated Press)
Donald Trump, left, and Ted Cruz argue a point during the Republican presidential debate.(Carlos Osorio / Associated Press)
Ohio Gov. John Kasich makes a point during the debate while Sen. Ted Cruz looks on.(Chip Somodevilla / Getty Images)
Sen. Marco Rubio, Donald Trump and Sen. Ted Cruz, from left, at the Detroit debate.(Chip Somodevilla / Getty Images)
Republican presidential candidates Donald Trump, left, and Sen. Ted Cruz participate in a debate sponsored by Fox News at the Fox Theatre in Detroit.(Chip Somodevilla / Getty Images)
Republican presidential candidates Donald Trump, left, and Sen. Ted Cruz participate in a debate hosted by Fox News in Detroit.(Chip Somodevilla / Getty Images)
Sen. Marco Rubio and Donald Trump argue during the Republican presidential primary debate at Fox Theatre in Detroit.(Carlos Osorio / Associated Press)
Donald Trump discusses Marco Rubio’s recent comments about his hands during Thursday’s debate in Detroit.(Paul Sancya / Associated Press)
Donald Trump speaks during the Republican debate.(Carlos Osorio / Associated Press)
Ohio Gov. John Kasich makes a point during the debate.(Paul Sancya / Associated Press)
Sen. Ted Cruz speaks during the debate in Detroit.(Carlos Osorio / Associated Press)
Marco Rubio during the Republican debate.(Carlos Osorio / Associated Press)
Donald Trump appears on a video screen at the Fox Theatre in Detroit.(Chip Somodevilla / Getty Images)
Republican presidential candidates Sen. Marco Rubio, Donald Trump, Sen. Ted Cruz, and Ohio Gov. John Kasich, participates in a debate sponsored by Fox News in Detroit, Michigan.(Chip Somodevilla / Getty Images)
The candidates prepare before the start of Thursday’s debate.(Paul Sancya / Associated Press)
The Fox Theatre in Detroit, setting of the latest Republican presidential debate.(Geoff Robins / AFP / Getty Images)
People arrive at Fox News in Detroit for the Republican debate.(Scott Olson / Getty Images)
A John Kasich supporter marches outside the Fox Theatre before the debate.(Chip Somodevilla / Getty Images)
Protesters march in front of Fox Theatre before the Republican presidential primary debate in Detroit.(Paul Sancya / Associated Press)
With their presidential hopes barely alive, Marco Rubio and Ted Cruz leveled a series of personal attacks Thursday night at front-runner Donald Trump, hoping an increasingly desperate effort will loosen the billionaire’s grip on the Republican nomination.
Tangling over immigration, foreign policy and Trump’s long, controversial business record, the candidates reached new heights of anger, vitriol and contempt as they collided on a debate stage in Detroit.
Trump taunted Rubio as “little Marco” and loosed a string of insults at Cruz: “Liar ... the lying guy up here ... lying Ted.”
Rubio, the Florida senator, portrayed Trump as a con artist, and Cruz repeatedly questioned Trump’s temperament and stability to serve as commander in chief. “We need a president who isn’t rash,” said the senator from Texas, “who doesn’t pop off at the hip.”
The fourth candidate onstage, Ohio Gov. John Kasich, spent much of the night chiding others for their tone, but he gently joined the pile-on, suggesting Trump was no different from any other politician who says one thing to get elected then does another in office.
The round-robin of assault and invective reflected a shift in strategy as increasingly agitated Republican leaders work to stop Trump.
That effort began in earnest earlier Thursday when the party’s 2012 nominee, Mitt Romney, delivered a blistering attack on Trump and offered a group endorsement of his opponents.
The hope, reflecting sentiments of the party establishment, is to collectively deny Trump enough delegates to win the nomination outright, allowing a preferred alternative to emerge at the GOP nominating convention this summer.
The all-against-Trump campaign was evident minutes after his rivals took the stage. Asked about his stepped-up attacks on the front-runner in the last week — over his business ethics, his spray-tan and even, implicitly, his manhood — Rubio responded that “if there’s anyone who ever deserved to be attacked that way, it’s Donald Trump.”
He cataloged the people and groups Trump has insulted during the campaign, then belittled Trump’s command of policy, referring to him as “someone who thinks the nuclear triad” — the systems used for launching U.S. weapons — “is a rock band from the 1980s.”
Trump, his voice thick with condescension, called Rubio a “little guy” who has lied about Trump’s record, and defended himself against a Rubio double-entendre about his small hands.
Much of the debate consisted of the candidates reprising familiar positions: Trump lamented trade deals that, he says, undercut American business and workers. Rubio called for lower taxes and regulations to spur jobs, while chiding Trump for manufacturing his clothing line overseas.
The face-off was also marked by the degree of personal animosity, the yelling and shouting, which prompted co-moderator Chris Wallace of Fox News to admonish at one point, “Gentlemen, you’ve got to do better than this.”
Undeterred, the candidates continued to swing away.
In a particularly heated exchange, Rubio renewed his attack on Trump University, a now-defunct series of get-rich real estate seminars that is the subject of numerous lawsuits.
He suggested the courses were a scam designed to enrich Trump while fleecing its students.
“The real con artist is Marco Rubio,” Trump fired back, suggested he had neglected his job as senator. “The people of Florida can’t stand him. He couldn’t be elected dog-catcher.”
After an extended back-and-forth, Cruz cut in. “Is this the debate you want playing out in the general election?” he asked, referring to pending litigation.
“Count to 10!” Cruz barked, chiding Trump for the repeated interruptions. “Count to 10!”
Trump at one point acknowledged he had changed his position on immigration, favoring the entry of more high-skilled workers into the U.S.
Asked by co-moderator Megyn Kelly of Fox News whether, in effect, he was pandering to voters by taking a seemingly hard line on immigration and other issues before later softening his positions, Trump replied, “I have a very strong core” but added, “I have never seen a successful person who was not flexible.”
The candidates delved only briefly into foreign policy, with Rubio pointing to Trump as he accused him of lacking the necessary seriousness to confront a complicated world.
“The next president of the United States is going to have eight years of a mess of a foreign policy to clean up,” Rubio said. “That’s why it can’t be Hillary Clinton, and, quite frankly, it can’t be someone who simply has not shown the intellectual curiosity or the interest in learning about these very complicated issues.”
Trump calmly dismissed Rubio without answering the critique. “I’ve gotten to know Marco over a period of time,” he said. “Believe me, he is not a leader.”
While Trump spent a good deal of the night on the defensive, he mostly kept his composure and lost none of his trademark swagger.
“They’re not going to refuse me, believe me,” he said. “If I say do it, they’re going to do it.”
All verbal attacks aside, the candidates did agree on one thing — somewhat surprisingly, given their nastiness: Each agreed to support the other should he prevail at the end of the primary season.
The first chance for Trump’s rivals to try to halt his runaway candidacy comes Saturday, when Kansas, Kentucky, Louisiana and Maine vote. On Tuesday, Michigan follows, along with Mississippi, Idaho and Hawaii.
However, the biggest test for the GOP field will be on March 15, when Rubio and Kasich face last-stand contests in their respective home states.
As always with Trump there was a soap-operatic element to Thursday night’s debate, as he faced Kelly for the first time since a confrontation last August.
Trump was angered in that first GOP debate when Kelly asked about his history of demeaning comments toward women. He subsequently lambasted Kelly as a bimbo and lightweight and seemed to suggest she was overly aggressive in her questioning because she was menstruating.
Trump then skipped a debate just before the Iowa caucuses in January, when Fox refused his request to remove Kelly as co-moderator.
Kelly and Trump engaged in a jocular exchange about a half hour into the session. “Nice to be with you, Megyn. You’re looking well,” Trump said, when Kelly posed a question about his immigration stance.
Kelly smiled, and the audience laughed along knowingly.
The debate was the first without Ben Carson, the retired neurosurgeon and a favorite of Christian conservatives.
He was never a serious contender of the GOP nomination and, bowing to the inevitable, announced on Wednesday he would not take part in the debate though he did not officially withdraw from the presidential race.
Times staff writer Michael Finnegan contributed to this report.