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Donald Trump just won today's South Carolina Republican primary, according to calls by NBC News, Fox News, and the Associated Press. This is the billionaire's most important win yet, and it firmly establishes him as the Republican presidential frontrunner.
The votes are still being counted, so the final margin isn't known. But the media outlets' quick calls of the race indicate that things weren't all that close.
If true, that's fantastic news for Trump, and the timing of his victory means it could have dramatic implications for the overall race. That's because the pace of voting is about to accelerate very quickly — so Trump's win here could mean he has momentum going into Super Tuesday on March 1, when 11 states will hold Republican primaries or caucuses.
But that's not all. Trump's Palmetto State win is also significant because he has won the first Southern contest. It seemed, in theory, that the evangelical, staunchly conservative Texan Ted Cruz could be more appealing to Southern voters than Trump, a New Yorker who is not particularly ideologically conservative or religious. Yet Trump's anti-immigration message — focused on "making America great again" — seems to have resonated here.
That could matter a great deal, because those Super Tuesday states coming up so soon are mainly Southern states. If Trump follows up his win today with similar wins in states like Georgia, Tennessee, Alabama, and Arkansas on Super Tuesday, he could rack up a pretty sizable delegate lead — and his remaining rivals would have to scramble to try and catch up.
If the field remains crowded, Trump could keep racking up delegates
The Republican nomination contest has entered a very dangerous phase for GOP elites. Only Donald Trump and Ted Cruz — both of whom the elites loathe — have won contests so far. And the upcoming calendar and delegate allocation rules could make it difficult for a mainstream contender like Marco Rubio to win many delegates if the field remains crowded, as the Upshot's Nate Cohn has written.
So, can Trump still be stopped?
The answer to that question could come down to one crucial dynamic: how quickly the GOP field shrinks in the next few weeks, and who gets knocked out of the race.
"What happens really is dependent upon the extent to which the field winnows," Josh Putnam, a University of Georgia lecturer and expert on nominating rules who runs the Frontloading HQ website, told me on Thursday. "So much of it is dependent on that one variable alone."
For instance, it's generally believed that Jeb Bush and John Kasich have been predominantly drawing votes from Marco Rubio. If that's true, the longer they stay in the race, the more difficult it will be for Rubio to win delegates on March 1. Though those states are all supposed to allot their delegates proportionally, several have set thresholds that candidates need to meet to qualify for delegates. So if Rubio is losing votes to Bush and Kasich, he risks falling below those thresholds. (That's why it was such good news for Rubio that Bush suspended his campaign Saturday night.)
Then there's Ted Cruz. Even if Trump beats him in many of the Southern Super Tuesday contests, he could perform strongly enough to win second place in many of them. But the back half of the primary calendar is filled with relatively few "red" states — instead, the biggest delegate hauls will be found in big blue states like New York, Pennsylvania, and California. And it doesn't seem likely that Cruz can be competitive with Trump in blue states.
The upshot is that, so long as the GOP field remains divided, Trump has a big opportunity to roll to a series of victories and rack up delegates. So, unless one clear challenger to Trump establishes himself soon, the outlook for his campaign will seem better than ever.
