Having defied political gravity with an unconventional campaign, Republican front-runner and novice politician Donald Trump broke another ironclad rule nine days ago: He skipped the debate ahead of the nation's first primary contest over a tiff with Fox News anchor Megyn Kelly, the scheduled moderator.

Then the celebrity billionaire -- whose campaign cornerstone is "winning" -- came in second to Texas Sen. Ted Cruz, his chief rival, in the Iowa caucus.

Rebounding from his tactical error in Iowa, however, Trump got in the first and last words in Saturday's ABC News Republican primary debate in New Hampshire, where he holds a double-digit lead ahead of the Feb. 9 primary. He returned to the spare-no-feelings style that has served him well with angry, restless Republican voters so far in the campaign.

Yet Trump was perhaps better served by the rhetorical beatdown contender Chris Christie laid on Florida Sen. Marco Rubio, the GOP's latest establishment favorite. Without a target on his back, Trump flew under the radar, for the most part -- he ranked second in Google Search trends during the debate, and didn't finish first in speaking time, both rarities -- and his 30-point polling average probably will remain intact.

"We're going to win with Trump. We're going to win," he said, asked to respond to allegations he doesn't have the temperament for commander-in-chief. "We don't win anymore. Our country doesn't win anymore. We're going to win with Trump. And people back down with Trump. And that's what I like and that's what the country is going to like."

That arguably was Trump's attempt to push back the narrative that he'd lost steam to Rubio, who was perceived to have left Iowa with momentum following a better-than-expected third-place finish. Despite leads in most national polls, a Public Policy Poll out last week showed Rubio gaining ground on the real estate mogul as the race tightened -- and as Trump accused Cruz of "stealing" the Iowa vote via dirty tricks aimed at fellow contender Dr. Ben Carson, who finished third.

But if Rubio was his main rival onstage, Trump didn't have to do much work to hold him off.

Christie attacked Rubio early and often, hammering the first-term senator for absenteeism on the job and called him out for repeating the same attack line on President Barack Obama several times within the debate's first hour.

By contrast, Trump stayed mostly in his lane, arguing that his self-described superior deal-making skill, coupled with his larger-than-life personality and ability to recruit top talent, was more than adequate for the Oval Office.

Trump was grandiloquent about himself, his temperament and his ability to serve. He needled Rubio ("If you notice, he didn't answer the question") and Cruz, the frenemy who bested him in Iowa. He traded blows with former Florida Gov. Jeb Bush, his chief antagonist, and slammed Hillary Clinton, the Democratic presidential front-runner.

While Christie did the dirty work of hammering Rubio, Trump reiterated his familiar themes of taking on China in trade ("They are sucking trillions of dollars out of our country"), replacing Obamacare ("I'll have something so much better"), returning waterboarding to the anti-terrorism toolkit and and reestablishing winning to a country he says doesn't do that much any more.

He did, however, have a few rough moments when Jeb Bush challenged him on the notion of eminent domain -- government seizure of private property for the greater good.

After Trump finished describing how the principle was good for the nation -- "Without it you wouldn't have roads or bridges," he said -- Bush chided Trump for using it to expand his casino empire, pushing out an elderly woman in the process.

Like a villain on the pro wrestling circuit, Trump took on the mainstream Republican audience when they booed him for challenging Bush and shushing the former governor in the process during the heated exchange.