Finally, in South Carolina on Thursday night, Donald Trump had a good, winning debate.

Not a flawless one — if Fox News GOP-pulse-taker Frank Luntz's focus group is any indication, Trump badly lost the exchange with Sen. Ted Cruz (Texas) over Canadian-born Cruz's eligibility to be president. Cruz was funny, and his knowledge of the U.S. Constitution is certainly firmer and more extensive than Trump's, but the fact that Cruz had to try to prove a tricky negative — there's no chance the "natural born" issue could hang over his potential general election campaign — meant it wasn't a clean win for Cruz.

It was an entertaining exchange, though, and if you turned the TV off after this question, you'd probably think Cruz won the debate:

But the debate went on for another two hours. And any good Cruz did for himself against Trump here was eroded greatly when he doubled down on his critique of "New York values."

The "birther" exchange, as Cruz termed it, may have been the moment for Luntz's South Carolina Republicans, but on social media, the "New York values" fight got the most attention. And Cruz came out of this one looking pretty shoddy:

Trump made Cruz look kind of like a jerk, but he also, uncharacteristically, came off as calm and measured. Then there was the substance of Cruz's attack on New York: Not only do plenty of conservatives live in Manhattan, contrary to Cruz's one-liner, but many of them are prominent commentators, financiers, and lawyers, some of whom Ted Cruz has visited to ask for money. Cruz's wife, Heidi, is a managing director at Wall Street giant Goldman Sachs. There's certainly nothing wrong with asking wealthy donors for money or being married to a successful banker, but it makes Cruz's harsh criticism of "New York Values" like "focus around money and the media" a real head-scratcher.

Why focus on Trump and Cruz, when there were five other candidates on stage? Because either Cruz or Trump will probably win the Iowa caucuses in two weeks. This was the second to last debate before the first votes are cast in the 2016 presidential race, one of the last chances voters in Iowa will have to see all the Republicans on the national stage. Both frontrunners had good debates. But Trump won the night.

Part of that is due to low expectations. "Trump's performances in these debates are never home runs — he's too undisciplined and unprepared for that," argues Chris Cillizza at The Washington Post. "But, this was, without question his best debate." Trump exceeded expectations; Cruz met them, probably.

Secondly, Cruz's strategy of handling Trump with kids' gloves seems to have come to an end. "I guess the bromance is over," Trump quipped in the post-debate spin room. No candidate yet undermined Trump's long-standing dominance in the polls. Maybe Cruz will be the first. But it's a pretty big gamble, with Iowa, if not the GOP nomination, at stake.

Maybe that's why the other five candidates mostly shied away from attacking Trump on Thursday night. Cruz, on the other hand, also got flak from the others, notably Marco Rubio, who after spending most of the debate hitting at Obama finally unleashed a largely unanswered volley of criticism at Cruz in the final minutes of the debate:

Almost everybody on stage in South Carolina had fine debate performances — the exceptions being Ben Carson and the obsequious moderators from Fox Business, Neil Cavuto and Maria Bartiromo.

Marco Rubio traded in his sunny optimism for angry broadsides — The Washington Post's Cillizza thought that worked well for Rubio; Nick Confessore at The New York Times did not; Chris Christie toned down the sarcasm just the right amount and consistently slapped at the U.S. senators on stage for boring viewers, showing why he's rising in New Hampshire; Jeb Bush had some decent moments; and Gov. John Kasich (Ohio) was quietly effective as the "reasonable" candidate on stage, though he marred that by talking about his record too much.

Overall, the Republican field, without Sen. Rand Paul (Ky.) on stage, seems to have abandoned the flirtation with being wary of foreign military intervention and opposing more intrusive government surveillance inside the U.S. The hawks won. On the stage in South Carolina, it was still midnight in America.

One of the few bipartisan applause lines in Obama's final State of the Union speech was his challenge to "make our politics reflect what's best in us, and not what's worst." Democracy "doesn't work if we think the people who disagree with us are all motivated by malice, or that our political opponents are unpatriotic," the president added, and it "grinds to a halt without a willingness to compromise; or when even basic facts are contested." The president said he believed in America because he believes in Americans.

On the stage in Charleston on Thursday night, Christie accused Obama of peddling to Americans "a fantasy land about the way they're feeling" in his State of the Union address. Cruz called Obama "an apologist for radical Islamic terrorism." The sitting president "does not believe that America is a great global power," argued Rubio, and has pursued "a foreign policy where we cut deals with our enemies like Iran and we betray our allies like Israel." Donald Trump said he "will gladly accept the mantle of anger" because the U.S. "is being run by incompetent people."

It was clear which view of America the Republican candidates subscribe to. We'll see in 11 months which America the majority of voters live in. As for now, Donald Trump finally won a debate.