The long-time frontrunner, real estate billionaire Donald Trump, and the candidate who’s recently displaced him atop the polls, retired neurosurgeon Ben Carson, faded into the background in a Fox Business News debate that quickly dove into the policy weeds and remained there.

In place of those political outsiders, more seasoned rivals — Florida Sen. Marco Rubio, Texas Sen. Ted Cruz, Kentucky Sen. Rand Paul and Ohio Gov. John Kasich, especially — flexed their mastery of nuance in a two-hour conversation that focused on economic policy.

Former Florida Gov. Jeb Bush, coming off a near-disastrous performance in the last such event, showed improvement. But it was arguably insufficient to calm donors who fear he can’t recover ground he’s lost to Rubio in the contest’s “establishment” lane.

More broadly, it’s unclear that anybody’s performance broke through enough — or, alternately, face-planted — to meaningfully alter the trajectory of the race. (Precisely one person in a 200-person CNN focus group reported switching allegiance in the wake of the event.) That matters because the GOP candidates won’t meet again on the same stage for more than a month, on Dec. 15 in Las Vegas.

And though the fourth Republican debate featured a slightly smaller cast — down to eight candidates from a high of eleven after some were demoted to the so-called undercard — the ideological range on display was as wide as ever.

The differences emerged in especially sharp relief during exchanges over immigration, Wall Street reform, national defense and trade.

Trump, who’s made mass deportation of 11 million undocumented immigrants the centerpiece of his platform, restated his intention to see it through. That prompted an interjection from Kasich. “Come on, folks,” he said. “We all know you can’t pick them up and ship them back across the border. It’s a silly argument. It’s not an adult argument.” And then Bush piled on: “Even having this conversation sends a powerful signal. They’re doing high-fives in the Clinton campaign when they hear this.”

Trump, for a moment back in the bullying form that defined his early debate performances, responded to Kasich, “I’ve built an unbelievable company worth billions and billions of dollars. I don’t have to hear from this man.” The comment elicited boos from the audience, as did a later taunt to former Hewlett-Packard CEO Carly Fiorina for “interrupting” — a sign that, at least for the assembled crowd, Trump’s bluster is aging about as well as room-temperature hamburger meat.

On immigration, Cruz stood up for Trump, a candidate he aims to overtake among hardcore conservatives. “If the Republicans join Democrats as the party of amnesty, we will lose,” he said. “I understand when the mainstream media covers immigration, it often doesn’t see it as an economic issue, but I can tell you for millions of Americans at home watching this, it is a very personal economic issue. I would say the politics of it would be very, very, different if a bunch of lawyers or bankers were crossing the Rio Grande — or if a bunch of people with journalism degrees were coming over and driving down the wages in the press.”

Notably, Rubio — like Cruz, the 44-year-old son of a Cuban immigrant — avoided the immigration clash altogether. His contribution to a 2013 immigration reform compromise that passed the Senate before dying in the House remains a major liability for him with his party’s right flank.

But the man who increasingly looks like the candidate to beat for the more moderate banner that traditionally confers the nomination itself had his conservative bona fides called out soon after. Paul challenged Rubio’s plans to expand child tax credits and bolster military spending as deficit-busters. “We have to decide what is conservative and what isn’t conservative,” Paul said, arguing that adding the tax proposal “to Marco’s plan for a trillion dollars in new military spending and you get something that looks to me, not very conservative.”

Rubio, who embarrassed Bush when his former mentor tried to attack him in the last debate, demonstrated once again his command of the stage. “I know that the world is a safer and a better place when the United States is the strongest country in the world,” he said, earning big applause.

Meanwhile, Fiorina turned in a characteristically crisp performance, though it’s not clear to what end. She called for replacing the Affordable Care Act with a system that allows states to manage high-risk pools; reducing the tax code to three pages; and dismantling the Dodd-Frank reforms adopted after the financial crisis. She once again framed herself as an outsider — “It’s not just about replacing a Democrat with a Republican,” she said at one point, “it’s about changing the status quo” — though she’s failed to maintain a share of the support that Trump and Carson are dividing between them.

A big question that will be answered in the days ahead was whether Bush managed to reassure those in his camp spooked by his last debate performance and his steady slide in the polls. The once-prohibitive GOP favorite adopted a hybrid strategy, scrapping with his rivals to earn more airtime after a relative shutout in his last showing while also lacing into Hillary Clinton, a tack more typical of a frontrunner.

Yet the discomfort in the spotlight that’s dogged him throughout the campaign also showed through on Tuesday night, as he struggled at times to get his points across — a presentation that suffered particularly in comparison to that of a highly polished Rubio. Bush’s inability to articulate a bigger vision, one that he himself acknowledged after the last debate, didn’t markedly improve. Especially odd, the candidate whiffed in the debate’s version of tee ball, the closing statement, pledging to overhaul care for veterans — an important cause, no doubt, but hardly the soaring stuff that sustains a winning presidential campaign.