Ron DeSantis was livid.
The super PAC supporting him had posted a trove of sensitive material, including strategic advice and research on his rivals, only days before the first debate of the 2024 campaign. The advice was, at times, so basic that it could come off as condescending: reminding the Florida governor to talk about his family, for instance, and prescribing how many times he should attack President Biden and the news media.
Mr. DeSantis erupted over the revelation, according to people told of his reaction, even though the posting of the documents online was meant to avoid running afoul of campaign finance rules. The advice memo, pilloried as “amateurish” within his extended orbit, was quickly taken down, along with the other documents, but the damage had been done. If he followed the advice laid out — including which rivals to hit — he would look like a puppet.
Campaigning over the weekend, Mr. DeSantis distanced himself from the memo. “I didn’t do it,” he said. “I didn’t read it. It’s not going to influence what I do.”
The episode was a self-inflicted wound by the broader DeSantis team that capped two months of difficulties for the Florida governor that have included dropping poll numbers, a new campaign manager and staff cutbacks. Now, Mr. DeSantis heads into Wednesday night’s event in Milwaukee looking to reclaim lost ground and avoid losing more, knowing that he is almost certain to be a major target for his rivals without Donald J. Trump on the stage.
It’s been clear for weeks that the debate would be a critical juncture; to prepare, Mr. DeSantis brought on a top Republican debate coach, Brett O’Donnell. But in some ways, a number of Republicans said, Mr. DeSantis is less in need of a breakout moment than of a stabilizing performance. Allies believe his top priority is to reassure skittish donors and supporters that he has the mettle to square off against Mr. Trump.
“This is a big moment for him, but he’s going to rise to it,” predicted Representative Thomas Massie of Kentucky, one of a few House Republicans backing Mr. DeSantis.
Mr. DeSantis has displayed some resiliency. Polls show that after months of attacks from Mr. Trump and weeks of unflattering headlines about campaign upheaval, many Republican voters still like Mr. DeSantis. He had the highest favorability rating of any Republican in this week’s Des Moines Register/NBC News poll in Iowa, even as he trailed Mr. Trump by 42 percent to 19 percent.
But his standing in the multicandidate race has slipped, with other candidates such as Vivek Ramaswamy and former Gov. Chris Christie of New Jersey appearing to make inroads in the race for second place.
“When he got in the race, he had the first license to be the alternative to Trump,” Brad Todd, a longtime Republican strategist, said of Mr. DeSantis. “But it was a license that had an expiration date, and I think that’s probably due.”
“It’s really his title to keep,” Mr. Todd added, but “it’s not a foregone conclusion he keeps it.”
Whether Mr. DeSantis can convert those favorable views into votes remains to be seen.
Advisers say Mr. DeSantis is focused on winning the nomination on the ground in Iowa and the other early states, outworking Mr. Trump and leveraging his well-funded super PAC to out-organize his rivals. But if the national perception of his candidacy does not improve, that task becomes significantly harder.
Publication of the debate-prep documents further sowed mistrust between Mr. DeSantis’s campaign and the super PAC, which he seeded with $82.5 million left over from his 2022 re-election. The anger is so palpable that one person who has advised the DeSantis campaign said the super PAC memo “almost seemed intentionally unhelpful.”
One line in the memo seemed to sting most: the suggestion that Mr. DeSantis defend Mr. Trump and bludgeon Mr. Chris Christie by accusing him of angling to become an MSNBC host with his frequent broadsides against the former president.
That is because Mr. DeSantis, who had been traveling to events in Iowa and New Hampshire organized by his super PAC and interacting with members of the group’s staff, had already been testing out a version of just such a line with various people in private, according to a person with knowledge of the matter.
The dynamics of a Trump-less debate stage on Wednesday are hard to predict. But the DeSantis campaign expects the governor to be the “center of attacks,” according to a guidance that his new campaign manager, James Uthmeier, issued in a memo to donors and allies over the weekend.
“We all know why our competitors have to go down this road: because this is a two-man race for the Republican nomination between Governor DeSantis and Donald Trump,” Mr. Uthmeier wrote.
But the description of the G.O.P. contest as a “two-man race” seems outdated, as Mr. DeSantis’s rivals have drawn far closer to him in many polls than he is to Mr. Trump. The super PAC memo advised the governor to take a “sledgehammer” to one rival, Mr. Ramaswamy, who has been climbing in some surveys.
Mr. Massie, who dismissed the memo as “not the smartest move,” said that Mr. Ramaswamy was more of a “curiosity” than a serious candidate.
“There is no way in hell people are going to elect someone as president — or to either party’s nomination — who they only found out about six months ago,” Mr. Massie said.
A spokeswoman for Mr. Ramaswamy, Tricia McLaughlin, responded by mocking Mr. DeSantis for urging Republican voters not to be “listless vessels” who blindly support Mr. Trump.
“Counter to what some candidates onstage say, we believe the American people are more than just listless vessels,” she said.
One Republican aligned with a rival to Mr. DeSantis described Mr. Ramaswamy, who has repeatedly come to Mr. Trump’s defense, as a wild card in the debate.
Much will depend on the questions the moderators ask of the candidates, and whether they try to steer the conversation to a referendum on Mr. Trump in absentia, forcing the candidates to talk about him.
Mr. Massie said that Mr. Trump’s absence would allow Mr. DeSantis to take unanswered “clean shots” at the former president’s record, and to assert his right to rebuttals when attacked by rivals, soaking up airtime.
“He’s got to be careful, I think, not to criticize the man, Trump,” Mr. Massie said. “Policy is Ron’s path to victory.”
Indeed, while Republican politics is rife with prognosticators saying that the way to beat Mr. Trump is to attack him, Mr. Christie has been doing just that for weeks, gaining in New Hampshire but not in national polls. Neither strategy to beat Mr. Trump — holding him close or a frontal assault — has proved surefire in the months before Labor Day, when the campaign season begins in earnest.
The race is “wide open” for the eight candidates onstage, said Henry Barbour, a longtime Republican National Committee member. But, he added, “it has to be a one-on-one race.”
If there’s more than one candidate not named Trump still in the race after the South Carolina primary, the fourth G.O.P. nominating contest, which is set for Feb. 24, 2024, Mr. Barbour said, “it’s almost a given that Donald Trump will have an insurmountable lead by the middle of March” in the all-important delegate chase.
With Mr. Trump missing, Mr. Todd, the G.O.P. strategist, said the debate had the potential to feel like an undercard ahead of a later marquee matchup.
“The debate in some ways will perform like a semifinal,” Mr. Todd said, with the goal being to advance to the next round. “Everyone knows Trump is in the finals. This is about who will be in the finals with him.”