Gov. Ron DeSantis of Florida is sharply cutting the size of his presidential campaign staff, reducing by one-third a payroll that had swelled to more than 90 people in his first two months as a candidate, according to four people with knowledge of the decision.

Two senior-level advisers to the campaign left earlier in July, and Mr. DeSantis shed roughly 10 staff members last week. He is letting go of another set of aides on Tuesday, bringing the total number reduced to 38 aides. Politico first reported on the latest reduction.

The Florida governor has struggled to gain traction in his early months as a candidate running against former President Donald J. Trump, losing ground in the polls as allies and donors have raised questions about the long-term strength of his candidacy.

Those questions came to a head after the first public glimpse of his campaign’s finances this month. It showed that Mr. DeSantis’s payroll was roughly double the size of Mr. Trump’s and that the governor was burning through 40 percent of the $20 million he had raised from April through June.

He entered July with just $9 million to spend on the primary race from his initial haul, and a significant portion came from donors who gave the maximum amount possible, meaning they cannot contribute again.

In a statement, Mr. DeSantis’s campaign manager, Generra Peck, said the changes followed “a top-to-bottom review of our organization.”

“We have taken additional, aggressive steps to streamline operations and put Ron DeSantis in the strongest position to win this primary and defeat Joe Biden,” she said.

Mr. DeSantis was on a three-stop fund-raising swing through Tennessee on Tuesday, which was interrupted by a car crash. Mr. DeSantis was uninjured.

The payroll reduction came on the heels of a donor retreat in Park City, Utah, where Mr. DeSantis convened some of his top supporters. His campaign officials and super PAC advisers made presentations about the state of the race.

Two people at the donor event said that despite the fact that the alarming campaign filing had dominated coverage of Mr. DeSantis heading into the weekend, there was very little talk of it by campaign officials in formal sessions. Instead, they focused on the notion that they were steadying the ship, making adjustments and trying to find ways to help Mr. DeSantis spread his message.

Ms. Peck’s leadership was a focus of some of the donors in private conversations among themselves, according to people familiar with the discussions. But the weekend ended with Ms. Peck, who has made herself indispensable to both Mr. DeSantis and his wife, Casey, still in charge.