DeSantis Debuts a Leaner Campaign. But Donors Have Their Doubts.

But Mr. DeSantis himself has yet to adopt his campaign’s newfound frugality. On Tuesday, he flew multiple trips on private planes to fund-raisers around Tennessee. The private flights help explain part of how the campaign has burned through cash in its first six weeks. His campaign’s first report showed that he had spent $179,000 in chartered plane costs, as well as $483,000 to a limited liability company for “travel.”

Some of Mr. DeSantis’s rivals have been eager to point out their cost-saving measures. On Wednesday, Nikki Haley tweeted a photo with her flight attendant under the hashtag #WeFlyCommercial.

What’s more, Mr. DeSantis and other parts of his operation showed little sign of a message shift.

In an interview with the radio host Clay Travis that aired Wednesday, Mr. DeSantis said that he would consider picking Robert F. Kennedy Jr., a conspiracy theorist and anti-vaccine candidate running as a Democrat, to work at the F.D.A. or the C.D.C. The stunning remark prompted criticism from some prominent conservative writers, including at The National Review, where staff had once sounded bullish on a DeSantis candidacy.

Later in the day, Mr. DeSantis’s campaign aide Christina Pushaw, who is known for fighting with reporters online, attacked the popular Republican Florida Representative Byron Donalds, who is Black, for criticizing his state’s new required teachings on slavery. By night’s end, the feud over Mr. Donalds devolved to the point where another DeSantis aide, Jeremy Redfern, got into a fight with a random Twitter user and posted her photo prominently in a tweet.

At a donor retreat over the weekend — at a luxury ski resort in Park City, Utah, hired out for $87,000 — donors and allies, including Representative Chip Roy of Texas, had tough conversations with both the governor and his wife, a close adviser, about the structure and management of the campaign, according to two people who attended the retreat.