Trump doesn’t need a majority of the GOP to win the nomination. Just a third.

In head-to-head matchups, some early 2024 polling shows Gov. Ron DeSantis of Florida, Trump’s potential rival, outperforming him with Republican voters nationally. But the Republican primary isn’t won in a national race — it’s won in a slog through individual states. If Trump can hang onto a third of his supporters in the states, he’d have a chance of pulling off another victory.

Trump’s skeptics aren’t wrong to question whether he can do it again. Trump’s support has continued to plummet after the Jan. 6 attack on the Capitol, a rocky presidency and a disappointing 2022 midterm election. Whether Trump’s base is as strong as he thinks is an open question, but it doesn’t have to be massive in order to win the primary.

The 2016 primary

When the 2016 Republican primary began, there were so many candidates that the networks divided debate nights into two separate segments: one for the stragglers, and one for the leaders in the polls.

In the debates among the top contenders for the nomination — dubbed the “varsity” debates by pundits — two candidates took the lead in opposing Trump as a semi-unified front: Jeb Bush, the candidate with the most money and institutional support, and Scott Walker, the former governor of Wisconsin. Walker, who had long been considered a favorite for the nomination, turned to Trump on the CNN debate state in September 2015 and told him, “We don’t need an Apprentice in the White House.” Bush, standing at a podium between Trump’s and Walker’s, nodded and grinned approvingly.

It didn’t work. Less than a week later, Walker dropped out, announcing that he wanted to help consolidate support behind a “positive, conservative message” that could “rise to the top of the field.” He didn’t mention Trump’s name, but his intent was clear: get the other dozen candidates to turn against Trump. With Walker out of the race, Bush took up the mantle of directly taking on Trump, who was consistently at the center of the debate stage in reward for his standing in the polls. Ted Cruz, meanwhile, initially had a public policy of keeping his opinion of Trump private.

Meanwhile, the rest of the field turned on one another in hopes of becoming the last guy standing against Trump.

As votes started trickling in, the Republican primary rules further helped him. Even when Trump took second place, he still racked up delegates. In February, Trump received all 50 delegates in South Carolina in reward for his 33 percent victory. Rubio and Cruz, who received 22 percent each, didn’t get any delegates. Bush, who placed fourth at 8 percent, decided to drop out of the race.

On March 1, considered the Super Tuesday of the primary, Trump received an average of 35 percent of the vote in the night’s primaries — but left with at least 254 delegates. Other than Trump, Cruz left the night in the strongest position of the fractured field: He had the second-most delegates at about 218, followed by Marco Rubio with 96.

Had Rubio dropped out before Super Tuesday, the clearest beneficiary would have been Cruz; Trump’s support had not yet permeated the entire Republican Party, and Cruz seemed like the strongest alternative to Trump.

The NBC poll also showed a significant portion of Rubio’s vote would have gone to Chris Christie, Carly Fiorina and Bush. But those candidates dropped out after the poll was released — and before Super Tuesday. So it’s reasonable to conclude that Cruz would have ended up with an even larger share of Rubio’s delegates, possibly allowing Cruz to get in front of Trump in the delegate count after Super Tuesday.

But it would be another two weeks before Rubio dropped out, leaving just Trump, Cruz and — trailing far behind — John Kasich. It took Trump more than three dozen caucuses and primaries before he managed to win with a substantial share of the vote. In the two weeks after Rubio’s departure from the race, Trump won Arizona and Cruz won Wisconsin. The next big primary was New York on April 19, which Trump won with 60 percent of the vote. Until that point, he received an average of about one-third of the vote in each contest.

After the New York primary, there weren’t enough delegates left on the calendar for either Kasich or Cruz to win the nomination, barring a contested convention. Trump had secured at least 845 delegates, while Cruz and Kasich combined had accumulated at least 666. Two weeks later, they would drop out of the race.

Proxy primaries

Trump didn’t face a primary in 2020 — in fact, states canceled their primaries altogether rather than host a potential challenge to Trump. But two years later, out of office, Trump got involved in primaries as a way of ensuring that the Republican Party remained loyal to him, even after he left the White House.

The Republicans best positioned to win in 2022 were incumbents; the next best thing was being a Trump-endorsed candidate.

Of 190 candidates for Congress and governor endorsed by Trump, compiled by FiveThirtyEight, only 11 failed to win elected office, either falling short in the primary, general election or runoff.

But that doesn’t tell the whole story. For starters, Trump endorsed at least 49 House candidates who ran unopposed. In cases like those, Trump’s endorsement was a symbolic show of solidarity — or, more cynically, an easy way for him to inflate the power of his endorsement.

He endorsed 18 candidates as challengers to incumbents or for open seats, and they averaged 50 percent of the primary vote share, with some candidates — like longtime GOP recruit John James — reaching up to 86 percent of the vote. But there was a major disparity between the most successful Trump-endorsed candidates and the least successful ones. Two of those 18 candidates qualified for the primary runoff by reaching 23-26 percent of the vote. In the runoff, neither cracked 32 percent: Madison Gesiotto Gilbert, who won the seven-person primary with 29 percent of the vote, went on to lose the general election. Bo Hines won the primary with 32 percent of the vote and ultimately lost the general election.

But Trump’s endorsement was still so potent because it virtually guaranteed that his endorsed candidate would receive support from at least a quarter of the primary vote — and usually at least one-third of it.

What this means

As Trump’s popularity continues to dive after a lackluster GOP primary, DeSantis inches up in the polls as the one person who can defeat Trump. But, as Trump proved in 2016, the biggest challenge for any would-be challenger is to meet him on the debate stage, where Trump’s charisma and confidence took down the biggest stars of the party, one by one.

Though the even bigger point in favor of Trump winning the nomination is that the Republican primary looks like it’s going to be crowded again. And early polling shows that Trump is again staking out that one-third of the vote in early states, even as he fails to command a majority.

As the primaries begin in earnest, the earliest polls show that, even as Trump’s popularity falls, the one-third of Republican primary voters who supported him through thick and thin — when he was a punchline in the early primary states and those who endorsed his chosen candidates in the 2020 primaries — still exist.

The question is now what happens to the other two-thirds of the vote. In 2016, that two-thirds was splintered among multiple candidates in the early states, while Trump consistently — yet slowly — racked up delegates with his small but mighty share of voters. Eight years later, Trump is a different person in the minds of many Americans. He’s no longer just a reality TV star running for president; rather, he’s a former president running for a second term. And his popularity since the early days of the 2016 campaign has skyrocketed, turning him into the most popular person in the GOP.

But when it comes to delegate math and the path to the nomination, his once-popularity and his record might not even matter — as long as his staunchest supporters stick by him.