For a non-incumbent (if former president), Trump has made short work of the primary calendar, basically annihilating any real competitors in record time without ever having to deign to step foot on a debate stage. The fact that he didn’t completely cruise to the nomination captures some of the hesitancy in the party that Julia highlighted, but at the end of the day, all Trump needs to do now is be more popular than Biden, who isn’t exactly the Prom King these days.

—Kaleigh Rogers, 538

I'm honestly not sure there is a clear way to go about establishing what Trump "should" be winning, Mary. On the one hand, polls had him at 61 percent, so 60 percent of the vote (as of now) is pretty good — especially if you consider he'll win the nomination easily by mid-March if this is the case.

Another benchmark would be the percent of the GOP electorate that calls themselves "part of the MAGA movement." According to preliminary ABC exit polls, that's about 44 percent of SC voters (50 percent said no and 6 percent were unsure). So by this benchmark, Trump is actually overperforming.

Too bad there aren't a whole lot of modern examples of former presidents + failed presidential candidates running in subsequent primaries, or else we could try to establish historical baselines. Trump's performance right now is somewhere between George H.W. Bush vs. Pat Buchanan and Jimmy Carter vs. Ted Kennedy. Both of those incumbents lost in the general.

—G. Elliott Morris, 538

I'm on the fence. As I pointed out, this would be panic-time for a sitting president running for reelection — evidence of a significant rift in the party. And it's not a mystery what that rift is — people in the Republican party who have reservations about Jan. 6, Trump's electability or his presidential temperament. At the same time, he has majority support in most polls, far outpacing any rivals.

—Julia Azari, 538 contributor

The first few primaries to me don’t seem to suggest the kind of strength that I would expect from a universally known, pretty well-liked (within his party) former president. So, is Trump doing well in this race, or is he just doing better than Haley? And does that mean anything for November?

—Mary Radcliffe, 538

The Republican presidential primary started out in territory pretty friendly to Haley. That changes after today, making the South Carolina primary a sort of last chance for the former Palmetto State governor to prove she actually has a path to the 1,215 delegates necessary to secure the GOP nomination. It looks somewhere between unlikely and impossible that she'll be able to pull that off.

It's all about the numbers. According to the polls, Trump leads Haley by about 30 points among likely Republican primary voters. But his delegate lead is what really matters — and it's likely to be even larger. That's because the South Carolina Republican Party awards its delegates on a winner-takes-all basis. About half the delegates will go to the winner of the statewide vote (almost certainly Trump) and the remainder will go to the winner of each of the state's seven congressional districts. With a 30-point statewide victory, Trump would probably win every district resoundingly; in 2016, the largest difference between Trump's statewide margin (10 points) and his margin in the most anti-Trump county (which he lost by 5 points to Marco Rubio) was only 15 points.

This is all disastrous news for Haley, who needs all 50 delegates from the state to be on track to win the Republican nomination. The competition on and after Super Tuesday will be even tougher. According to the math powering 538's delegate benchmarks, Trump is leading Haley by around 57 points in California and 69 in Texas, the states with the largest delegate hauls on Super Tuesday. Those states also allocate delegates on a winner-takes-all basis, as long as a candidate wins at least 50 percent of the vote.

The primary, in other words, is functionally over. But because Trump has not yet clinched a majority of delegates, Haley's campaign technically has a chance of winning. It's just very, very low.

—G. Elliott Morris, 538