Eric J. Tanenblatt, a top fund-raiser for former Gov. Nikki Haley of South Carolina, woke up Thursday morning in his Milwaukee hotel room to dozens of enthusiastic text messages and emails from donors expressing admiration for Ms. Haley’s performance, particularly her command of foreign policy and handling of questions about abortion.
“Donors who have been sitting on the sidelines are now taking another look,” said Mr. Tanenblatt, an Atlanta businessman who has known Ms. Haley since she was a state legislator and attended the debate Wednesday night. “Obviously I am somewhat biased, but I think last night was a really good night for Nikki Haley.”
Mr. Tanenblatt was not alone in his assessment. In conversations with more than a dozen Republican donors — including undecided backers and some who support other candidates — Ms. Haley was singled out as the night’s standout. The question now becomes whether her debate performance will translate into dollars.
For years, the Republican money class has been seeking an alternative — any alternative — to former President Donald J. Trump. In some ways, donors were the most consequential audience for Wednesday night’s debate, and many of them, including those who have not yet backed a candidate this cycle, were in Milwaukee.
While the official fund-raising totals won’t be known until October, when campaign quarterly filings are due, there were signs within hours of the debate — flurries of text messages, requests for introductions to campaigns and reports of fresh contributions — that the candidates’ performances, even if they might not change hearts and minds, could move piles of cash.
A spokeswoman for Ms. Haley declined to release detailed numbers, but said the campaign had raised more money online in the 24 hours after the debate than it had on any day since the campaign started. “The response to Nikki’s debate performance has been overwhelming,” said the spokeswoman, Nachama Soloveichik.
Former Vice President Mike Pence, whom the donors also identified as having a good night onstage, also saw an uptick, according to his campaign. Marc Short, a top adviser to Mr. Pence, said it had taken in at least 1,000 new contributions overnight. While most were smaller donors — valuable because they can sustain a campaign in the long term — “the bigger breakthrough last night was the major donors,” he said, including some who had funded other candidates but held back on Mr. Pence.
“I think there’s been a large number of supporters who have been on the sidelines but have been looking for some of that spark,” Mr. Short said. “I think many of them saw that last night.”
The immediate feedback reflected the traditional sympathies of major Republican donors. They favored candidates who they felt came off as authoritative but not obnoxious, with established résumés and hawkish foreign policy views. They also, naturally, tended to see their preferred candidates’ performances through hopeful eyes.
These tendencies have proved to be blind spots before, especially in the face of the unwavering support of the small donor base that remains fiercely loyal to Mr. Trump. Several major donors downplayed the significance of the immediate returns, saying that no debate-dollar bump could surmount Mr. Trump’s popularity. Some who attended the debate described it as something of a social occasion or a sideshow.
Unsurprisingly, the candidate who most defended — and sounded like — Mr. Trump on Wednesday night, Vivek Ramaswamy, was also the candidate who most rankled the high-dollar donors. Several of them said they thought Mr. Ramaswamy, an entrepreneur and author, had overplayed his hand, citing his bombast and confrontational style.
“Vivek made a complete jackass out of himself,” said Andy Sabin, a major donor to Senator Tim Scott of South Carolina. “He is so clueless about what’s going on in this country.”
But his performance appeared to have appeal for some small-dollar donors. A spokeswoman for Mr. Ramaswamy, Tricia McLaughlin, said the campaign raised $625,000 in the 24 hours after the start of the debate — the biggest single fund-raising day of the campaign, with an average donation size of $38.
“Unlike some donor-favorite candidates onstage,” Ms. McLaughlin said, “Vivek is not worried about what the donor class has to say about his politics and performance, which is why he is unconstrained in speaking the truth.”
Mr. Sabin said he thought Mr. Scott had “done what he was supposed to do,” but the crowded, fast-paced format, in which candidates frequently talked over the moderators, made it hard for Mr. Scott to stand out. Money is less of a concern for Mr. Scott than for Mr. Pence or Ms. Haley: His campaign had $21 million on hand at the end of June, and groups supporting him have spent tens of millions of dollars on advertising in the early states.
“Tim stayed out of trouble and out of the fray, had good answers,” Mr. Sabin said. “He probably should have been more involved in this, but I don’t think that had anything to do with him.”
Gov. Ron DeSantis of Florida, who went into the debate with the highest poll numbers of any candidate on the stage, was also quieter than many had expected.
Some unaffiliated donors said it was a missed opportunity for Mr. DeSantis. Among the backers of other candidates, Bill Bean, an Indiana businessman and longtime supporter of Mr. Pence, said Mr. DeSantis “did not have that moment where he just separated himself from the whole field that I think some people were looking for.”
The days after the debate kicked off a major slate of campaign travel and new ads for Mr. DeSantis, according to Jay Zeidman, a major DeSantis fund-raiser. “We view this as the turn of a new chapter,” he said — a reference, in part, to the turbulence of the governor’s campaign in recent months, as his poll numbers have lagged. Mr. DeSantis’s super PAC, Never Back Down, confirmed that it would spend $25 million on ads in Iowa and New Hampshire in the next two months, a buy that was first reported by The Washington Post.
Mr. Pence, who has struggled to gain traction in the race and still lags far behind his rivals in fund-raising, spoke the most of any candidate on the stage last night, and many donors took notice.
“There was a lot of energy there,” said Mr. Tanenblatt, the Haley donor. “I think that surprised people.”
Several bundlers and donors — some of whom spoke on the condition of anonymity because they still plan to support Mr. Trump — suggested that Mr. Pence’s performance and steadfast appeal to evangelicals were likely to help him in Iowa, which is crucial to his campaign.
Before Wednesday’s debate, Mr. Bean, who has given $100,000 to a super PAC supporting Mr. Pence, hoped that Mr. Pence would have the opportunity to “show the American people who he really is.”
That objective was largely met, Mr. Bean said, although he felt the debate format was too fast-paced and chaotic to give any candidate enough time to cover significant topics.
“The biggest thing that was accomplished last night,” Mr. Bean said, was that Mr. Pence “moved past the Jan. 6 issue, which I thought was probably the biggest single thing out there that he had to do.”