Here are the key moments from the debate that brought Republican presidential candidates head-to-head in North Charleston, S.C. on Jan. 14. (Sarah Parnass/The Washington Post)

The seven leading candidates for the Republican presidential nomination debated for the sixth time in the 2016 race Thursday night in South Carolina. I watched -- and picked the winners and the losers of the night that was. They're below.

Winners

* Marco Rubio: The Florida senator has clearly been taking notes from Donald Trump. Rubio came out hot from the start -- channeling the anger of the Republican base much more effectively than he has in past debates. He also kept his message laser-focused on bashing President Obama and Hillary -- an approach that allowed him to look magnanimous and big.

Rubio also re-proved his ability to drop the opposition research book on an opponent, unloading on Ted Cruz as a flip flopper in the final moments of the debate. "That is not consistent conservatism," Rubio said of Cruz's voting record. "That is political calculation."

Rubio also benefited from the fact that, despite all of the pre-debate predictions that he would be at the center of attacks from other establishment figures, he barely had a glove laid on him. Even Chris Christie, who's never seen a showdown he didn't want to be part of, side-stepped a chance to unload on Rubio's lack of experience in elected office.

* Donald Trump: Yes, Cruz got the better of him on the citizenship back-and-forth -- although the fact that a question about the Texas senator's eligibility to be president was the third one asked in the entire debate amounted to a win for Trump. And, yes, Trump's answer on a tariff against China was, well, hard to understand (to be kind.)

But, unlike in the previous five debates, Trump seemed engaged throughout.  He interjected -- like in the conversation about corporate inversions -- where it made sense for him to. His response to Cruz's attack on "New York values" was an effective piece of political rhetoric. His insistence that he is "very angry" because of the mismanagement of the country worked well, too.

Trump's performances in these debates are never home runs -- he's too undisciplined and unprepared for that. But, this was, without question his best debate.

* Ted Cruz: Like Rubio, the Texas senator is just good at this.  He owned Trump on a back-and-forth over questions about his citizenship -- and did it with a smile on his face. As he has done in each of the previous debates, Cruz showed an appealing policy (and political) profile for conservatives still looking for a candidate.

Donald Trump called Ted Cruz's comments about "New York values" offensive during the Jan. 14 GOP debate in Charleston, S.C. (Fox Business Channel)

Cruz was knocked back somewhat by Trump over the "New York values" attack -- hard to look like you are on the wrong side of those who helped rebuild New York City after 9/11 -- and got beaten at his own game by Rubio when it came to voting records. It wasn't Cruz's strongest debate but his "average" performance is still pretty high.

* Seven-person debates: Sure, Rand Paul and Carly Fiorina didn't like it, but the truth is that limiting the number of people on the debate stage makes for a much more watchable experience. More debates, fewer people in them!

* Commercials: Four commercials! Okay! My bladder thanks you, Fox Business!


The Republican presidential candidates (Photo by Andrew Burton/Getty Images)
Losers

* Ben Carson: I mean...words fail.  The neurosurgeon has often looked out of his depth in these debates but never more so than tonight. He spoke, well, almost never. And, when he did manage to get the floor, he talked about the threat from an electromagnetic pulse. Um, okay. Carson's trend line in this race has been steadily downward for the last month. Nothing he did tonight will change that.

* Neil Cavuto/Maria Bartiromo: Look, moderating debates -- especially at this level with this number of candidates -- is hard. But, the key to making these debates work as they should is to force the candidates to get off their talking points -- usually by asking pointed follow-up questions or allowing the candidates to go at one another. There was way too little of either in this debate, meaning that we didn't learn as much about who the candidates really are (and what they really think) as we might have.

* Two-hour debates:  A debate that starts at 9 p.m. on the East Coast is tough enough. One that ends at 11:30 p.m. is beyond the pale. Can't we limit these things to a hard two hours?  Name one person who would oppose that.

* Fashion risks: 7 dudes. 7 dark suits.  6 white shirts. 4 red ties. 3 blue ties.  I mean, can't we shake it up even a little bit?  How about a gray suit? A purple tie?  Some stripes? (Shouts to Neil Cavuto's wide pinstripe suit; not my style but I applaud zigging while everyone else zags.)