Not long after the new chairman of the Republican Party in Hawaii was elected in May, he received a voicemail from none other than Donald J. Trump.
“It’s your all-time favorite president,” Mr. Trump told the chairman, Tim Dalhouse. “I just called to congratulate you.”
The head of the Kansas G.O.P. received a similar message after he became chairman. The Nebraska chairman had a couple of minutes and a photo arranged with the former president during an Iowa stop. And the chairman of the Nevada Republican Party, Michael McDonald, who had served as a fake elector for Mr. Trump after the 2020 election, was among a group of state party officials who were treated to an hourslong Mar-a-Lago meal in March that ended in ice cream sundaes.
Months later, Mr. McDonald’s party in Nevada dramatically transformed the state’s influential early contest. The party enacted new rules that distinctively disadvantage Mr. Trump’s chief rival, Gov. Ron DeSantis of Florida, by effectively blocking the super PAC he relies upon from participating in the state’s new caucus.
Mr. McDonald has tilted the rules so significantly that some of Mr. Trump’s opponents have accused the party of manipulating the election for him — and have mostly pulled up stakes in the state entirely.
As Mr. Trump dodges debates and is regularly seen on his golf courses in branded white polo shirts and red MAGA hats, it can seem that he is bypassing the 2024 primary fight entirely. He has done relatively few public campaign events until recent weeks. But Mr. Trump and his political team have spent months working behind the scenes to build alliances and contingency plans with key party officials, seeking to twist the primary and delegate rules in their favor.
It amounts to a fail-safe in case Mr. DeSantis — or anyone else — scores a surprise victory in an early state. And it comes as Mr. Trump faces an extraordinary set of legal challenges, including four criminal indictments, that inject an unusual degree of uncertainty into a race Mr. Trump leads widely in national polling.
“They’ve rigged it anywhere they thought they could pull it off,” said Ken Cuccinelli, a former Trump administration official who founded Never Back Down, the pro-DeSantis super PAC that was essentially ousted from the Nevada caucus.
The maneuvering is the type of old-school party politics that Mr. Trump, who cut his teeth in the machine politics of 1970s and 1980s New York, relishes and knows best: personal calls and chits, glad-handing, relationships and reprisals. Advisers say that in contrast to some tasks, getting him to make those calls is a breeze. Plus, the seemingly arcane issue of delegate accumulation — tallying up formal support in the states to secure the nomination at the party convention next summer — is deeply personal to Mr. Trump after he was outflanked in exactly this fight in 2016.
Then, a better-organized Senator Ted Cruz of Texas worked Trump-skeptical state parties to win more delegates even in some places where he had lost at the ballot box. Mr. Cuccinelli was one of Mr. Cruz’s top delegate hunters at the time. Now, surrounded by a more experienced team and the authority of a former president with loyalists entrenched nationwide, Mr. Trump is doing to Mr. DeSantis exactly what he once accused Hillary Clinton of doing to Bernie Sanders: bending the system in his favor.
Mr. Trump’s backroom campaign reveals the extent to which he has become the establishment of the Republican Party.
“This is the kind of stuff that’s not talked about in the news,” said Scott Golden, the chairman of the Tennessee Republican Party, who was invited to speak briefly in private with Mr. Trump when the former president visited his state this spring. “This is important stuff. It is ultimately about making sure your person is the nominee.”
In presidential primaries or caucuses, voters’ casting of ballots is only the first step. Those elections determine the individuals — called delegates — who go to the national party convention to formally choose their party’s nominee. The rules each state uses to allocate delegates and bind them to particular candidates can shift from year to year, and the people in charge of those rules are otherwise obscure state party officials.
Wooing those insiders can be crucial. Among those who attended the Mar-a-Lago dinner in March was Alida Benson, then the executive director of the Nevada Republican Party. Now she is Mr. Trump’s Nevada state director.
At one point, Mr. Trump’s campaign warned state parties nationwide about the legal risks of working with super PACs. In the past, super PACs have generally been allowed to organize and advertise in both primaries and caucuses. But in Nevada, a new rule was enacted that barred super PACs from sending speakers, or even literature, to caucus sites, or getting data from the state party.
The unstated goal: to box out Never Back Down.
Alex Latcham, who oversees Mr. Trump’s early-state operations, called the Nevada party’s moves especially sweet. He noted that Nevada is the state where the super PAC’s largest donor, Robert Bigelow, lives and where its chairman, Adam Laxalt, just ran for Senate.
“Not only is it a strategic victory, but it’s also a moral defeat for Always Back Down,” Mr. Latcham said, purposefully inverting the group’s name.
Advisers to Mr. DeSantis, known for his bare-knuckle tactics in Florida, have complained about an imbalance in the playing field.
“I don’t think they play fair,” said James Uthmeier, Mr. DeSantis’s campaign manager.
Mr. Cuccinelli accused Mr. Trump of hypocrisy. “No one has tried to rig the rules like Donald Trump has been doing here at least in a very long time,” he said. “And no one has ever done it who, in other circumstances, complains about the rules being rigged.”
Mr. Latcham called that “sour grapes on behalf of less sophisticated candidates or their organizations who were outworked and outmaneuvered. I mean, the reality is this is politics.”
Just how tilted is the field in Nevada now? Mr. DeSantis’s campaign won’t even say if he will apply to be on the ballot, and no serious candidate or super PAC has spent a dollar on television ads there since late June. Mr. McDonald, the state party chairman, claims neutrality but remains one of Mr. Trump’s closest allies. He and the Nevada G.O.P. did not respond to requests for comment.
Perhaps the most significant change in the primary rules took place in California. Republican officials in the state, whose primary was moved up to Super Tuesday by Democrats in the Legislature, adopted a set of rules over the objection of DeSantis allies that will award all 169 of its delegates to any candidate who tops 50 percent of the vote statewide — a threshold only Mr. Trump is currently anywhere near.
“By nature, President Trump is a gambling type of guy, and I think to have that opportunity is certainly appealing to him,” Jessica Millan Patterson, chairwoman of the California Republican Party, said of a potential delegate sweep.
Previously, each of the state’s 52 congressional districts delivered delegates independently, allowing candidates to cherry-pick more favorable political terrain. The change caused Never Back Down, the pro-DeSantis super PAC, to essentially give up on California, halting a door-knocking operation that had already visited more than 100,000 homes in the state.
Ben Ginsberg, a longtime Republican lawyer and one of the party’s foremost experts on delegates, called California’s move one of the most consequential changes on the calendar.
“It gives him an advantage that a front-runner has never had before to absolutely wrap it up by Super Tuesday,” Mr. Ginsberg said of Mr. Trump.
Behind the scenes, Mr. Trump’s campaign worked to shape California’s rules, contacting at least some party executive committee members directly. One person who helped craft the rules in California to make it harder for Mr. DeSantis to accumulate delegates was Kevin McCarthy, the former House speaker, who had for months sought to stay in Mr. Trump’s good graces in whatever ways he could short of a formal endorsement. In the end, Mr. Trump did not return the favor, staying on the sidelines as Mr. McCarthy was ousted this month as speaker.
At the center of the Trump delegate operation is a low-profile former White House aide, Clayton Henson. He has traversed the country for months on Mr. Trump’s behalf to establish a beachhead with party officials. This spring, on the same April day President Biden announced his re-election run, Mr. Henson plopped himself on the couch in the lobby of the Omni hotel in Oklahoma City, where the Republican National Committee was holding a training session.
He sat there all day, and the next, texting and pulling aside state party leaders for quick introductions. Other campaigns were absent that day — and have been for many of the months since.
“Clayton’s met with many of us,” said Eric Underwood, the Nebraska G.O.P. chair, who recently went to see Mr. Trump in neighboring Iowa. The campaign had arranged a few private minutes backstage; he pitched a future Nebraska visit. In contrast, Mr. Underwood said he had to personally push through a crowd to buttonhole Mr. DeSantis at the most recent R.N.C. meeting in Wisconsin.
Another state that has shifted its delegate rules is Michigan. While those changes came about after the Legislature moved up the primary date, state Republicans have implemented a complicated dual primary and caucus, with many of the delegates determined by a system seen as favoring Mr. Trump.
“It’s a slam dunk for Trump,” Jason Roe, a former executive director of the Michigan Republican Party, said of the shift. “I don’t think it’s a mistake that Trump-aligned party leaders engineered that.”
Mr. Trump’s backroom advantage — operating effectively as a party boss, leveraging relationships built during his presidency — is cover for his operational disadvantages, especially in Iowa. Mr. DeSantis’s team believes a defeat of the former president there would reset the race, and the governor is increasingly betting his whole candidacy on that.
Mike Brown, the Kansas chairman, said he had communicated regularly with Mr. Henson for more than six months as Kansas became a winner-take-all primary on March 19. It is the type of high-stakes early contest Mr. Trump’s advisers have favored even if they didn’t press for this particular move. For some other campaigns, Mr. Brown had to reach out to the R.N.C. for contact information.
“I received a call from folks connected to DeSantis,” Mr. Brown recalled. “Two very nice ladies who I can’t remember their name right now.”
Nicholas Nehamas contributed reporting.