President-elect Donald Trump enters Mar-a-Lago’s White and Gold Ballroom on Dec. 20, 2016, after a speech to the World Affairs Council of Palm Beach by David Shedd, former acting director of the Defense Intelligence Agency. (Bruce R. Bennett/The Palm Beach Post)

The women of the Palm Beach Habilitation Center had whispered among themselves that President Trump might pop in for their Hab-a-Hearts Luncheon at Mar-a-Lago, Trump’s luxurious private club.

“It was Presidents’ Day at the president’s house and the president was in town. Then, by golly, he showed up,” said Tina Philips, president of the center, a charity that provides job training and other services to adults with disabilities. “He took the microphone and talked to the group, and the ladies all went wild. He was in a very supportive crowd.”

It was a lucrative guest appearance for the group, which sold about 30 extra tickets, at $250 a pop, to additional attendees expressing excitement about a potential Trump sighting, Philips said. The group took in about $13,000 extra.

Trump’s club also made more money, since, according to groups that hold events there, its charges are based on the number of guests. The charity paid about $46,000 for food and to rent the Donald J. Trump Grand Ballroom, up about $4,000 from last year, Philips said.

Mar-a-Lago will soon close for the season, as Palm Beach’s wealthy snowbirds return north. That will bring an end to one of the oddest experiments in modern American politics — in which a sitting president has become a moneymaking attraction for his own private business.

In the six months since his election, Trump’s presence, or possible presence, became a ticket-selling draw generating extra cash for his customers and himself. The season also showed that the Trump effect can cut both ways, with one charity that faced criticism for hosting an event there experiencing a decline in ticket sales.

The president arrives at Mar-a-Lago during the Gateway for Cancer Research St. Patrick’s Day Party on March 17. (Meghan McCarthy/Palm Beach Daily News via ZUMA Press/Alamy)

The Washington Post identified more than 45 events since Election Day in which outside groups paid to rent space at Mar-a-Lago. Hedge-fund investors noshed by the pool. Zoo animals prowled for the entertainment of donors. Men in military gear dropped from a helicopter near the lakefront cocktail bar and stormed a lawn full of socialites as part of a benefit for the Navy SEAL Foundation.

In at least 10 of those cases, the events turned out to be a little bigger, and to raise a little more money, than in past years, according to interviews with event organizers. That often meant that they paid Trump’s club a little more money.

The reason, some organizers said, was that Trump’s event customers could offer the grandeur of the presidency as an added attraction for potential attendees. The trend is likely to continue next year, as some charities planning Mar-a-Lago events for the 2018 season are hoping the dates they book coincide with times that Trump is staying at the club.

“Now that you have all this security, it just creates [this sense of], ‘You’re special by being there,’ ” said Jennifer McGrath, executive director of the charity Hearing the Ovarian Cancer Whisper. The group’s late-January luncheon at Mar-a-Lago drew 75 more people than last year, McGrath said.

“Now that it’s the president’s winter home, there’s that great chance that he might pop into your event,” she said. “And that’s kinda good, too.”

The Trump connection has not been all good for some of Mar-a-Lago’s charity customers.

The Dana-Farber Cancer Institute’s February gala, which attracted criticism because Trump’s executive order on immigration had affected so many doctors, drew about 100 fewer people than in 2016, making the institute the only charity contacted by The Post that reported a decrease in attendance from its Mar-a-Lago event a year earlier. Proceeds from the annual event dropped by $50,000, the group said.

The institute’s leaders promised to avoid “controversial” venues in the future, and on Friday, a spokeswoman said the group is moving next year’s gala to the Breakers, the only other major venue in tiny Palm Beach.

Also Friday, the Palm Beach Daily News, the island’s premier chronicler of gossip and social events, reported that three additional charities that have held events in the past at Mar-a-Lago, including the Miami-based Bascom Palmer Eye Institute, have opted for other locations next year. Officials from Bascom Palmer, whose guests for an early-March gala at Mar-a-Lago were greeted by Trump outside the event entrance, confirmed that it would hold its two events next year at the Breakers.

Trump’s private company, the Trump Organization, did not answer a list of detailed questions about the season’s events. White House officials did not respond to requests for comment.

The president and first lady Melania Trump arrive at Mar-a-Lago on Feb. 4. for the 60th annual Red Cross Gala. (Susan Walsh/Associated Press)

The prominent role Trump has taken at the center of his private club’s events business illustrates the extent to which he stands to make money from the presidency, a key concern that has been raised by ethics experts and Democratic lawmakers. Although the president says he has given up day-to-day management of the company, his decision to retain ownership means he remains its beneficiary as Mar-a-Lago members, event hosts and attendees pay for the opportunity to attend events where they might well encounter the president.

Mar-a-Lago, the palatial 1920s estate that Trump bought in 1985 and turned into an exclusive club 10 years later, has already become a point of controversy in the early months of this unusual presidency.

Soon after Trump won the election, the club doubled its initiation fee to $200,000, according to media reports, restoring the amount to its pre-recession level. As president, Trump has taken seven trips to the luxury waterfront resort, often for a quick weekend getaway and a few rounds of golf, with his staff, motorcade and Secret Service detail in tow. In addition to the travel costs, taxpayers have footed the bill for security around Trump’s club so it can double as a secondary presidential office and home.

(Peter Stevenson/The Washington Post)

During the busy social season of glitzy dances, dinners and galas that runs from December to March, Trump or his wife, Melania, attended at least nine charity events, by The Post’s count.

At some of the biggest events, Trump was the center of the night’s attention. At the American Red Cross’s Versailles-themed ball in February, Trump stood at a lectern with the presidential seal as waiters and musicians milled about in Marie Antoinette-era wigs.

“I don’t think I’ve ever seen the room looking more beautiful — perhaps at our wedding — right, Melania?” Trump told the crowd.

This was a familiar scene for Trump at Mar-a-Lago, where the former reality-TV star had loved playing the role of owner, a bona fide star among the merely wealthy. This year, he was far more than that.

At the Dana-Farber gala, Trump and his entourage entered just as musician David Foster was starting his performance, drawing a huge ovation and forcing the singer to pause and acknowledge a bigger star.

“Well, either I have the best timing in the world, or the worst timing in the world,” Foster quipped, according to a report on the health news site Foster carried on, the site reported: “In spite of the one hundred armed men that are now in the room, we’re going to try to have some fun.”

At other events, Trump made much briefer appearances. He and Melania Trump dropped in to see volunteers setting up for the American Cancer Society benefit in February, posing for pictures but leaving before the event began, according to the group.

Other Trump family members have stepped in at times to help boost events’ prestige. The Big Dog Ranch Rescue’s “Wine, Women and Shoes Luncheon” in March included not only a dog fashion show but a speech from Lara Trump, the wife of the president’s son Eric. She is to co-chair the event next year with Georgina Bloomberg, the equestrian daughter of billionaire former New York mayor Michael R. Bloomberg.

Lara Trump did not respond to requests for comment. Bloomberg said the allure of Trump could be a welcome draw for a good cause looking to raise more money. “It’s nice to get some people, who wouldn’t otherwise go to a dog rescue, to come to your event just because someone’s gonna be there,” she said.

Even when he was not around, the president’s unpredictable schedule imbued the club with a will-he-or-won’t-he mystique that Palm Beach’s event-hoppers found difficult to ignore.

“It’s the president’s home. It’s the ‘winter White House.’ And people are obviously hoping that he will show up,” said Michael Barnett, the chairman of the Palm Beach County Republican Party. The local GOP’s Lincoln Day dinner was held at Mar-a-Lago, where officials had hinted that Trump might appear — sending an online invitation showing Abraham Lincoln wearing a “Make America Great Again” hat with the message: “Speaker to be announced.”

Trump didn’t show. The health-care bill was suffering a near-death experience, and the president stayed in Washington. Melania Trump attended instead, although her presence was fleeting: She stayed for about 15 minutes at a VIP reception featuring Florida Gov. Rick Scott (R) and pro-Trump YouTube stars Diamond and Silk.

Still, the event sold out, drawing 692 people who paid at least $300 per ticket, Barnett said. Attendance was up a little from last year, and Trump’s club made a little more, too. The GOP paid $150,000 for the dinner, about $10,000 more than in 2016, Barnett said.

But, Barnett said, the Florida GOP saves money in other ways. Before Trump ran for office, the group had to spend $5,000 a year sending out invitations to the dinner. Now that the event is at the president’s house, the group doesn’t have to, he said. “We sent out an email blast. We put out notifications on Facebook,” Barnett said. “We sold out within a couple of weeks, and we had about 300 on the waiting list.”

A view of Mar-a-Lago in November from the new beach club Trump built. (Mary Jordan/The Washington Post)

Some organizers described their Mar-a-Lago events as apolitical, saying the space is too lovely and the staff too friendly for them to stay away. The Breakers, a five-star hotel a few miles north of Trump’s club, is the only other gala-size facility on the island. Unlike Mar-a-Lago, however, it does not come with a presidential seal of approval. A spokeswoman for the Breakers said the hotel’s business has not been affected by Mar-a-Lago.

Trump’s club cannot always avoid its link to the highest rungs of American power. After a North Korean missile test in February, Trump, Japanese Prime Minister Shinzo Abe and their top aides convened a strategy session on the club’s open terrace as nearby diners snapped photographs. “Wow.....the center of the action!!!!” club member Richard DeAgazio wrote on Facebook.

Trump’s first appearance of the season at Mar-a-Lago was shortly before Christmas, when the president-elect popped into an event that the World Affairs Council of Palm Beach was hosting in the club’s White and Gold Ballroom.

“Is he doing a good job?” Trump asked the crowd, referring to David Shedd, the retired Defense Intelligence Agency acting director who was a guest speaker at the event, according to the Palm Beach Daily News. “He better be; he’s on my committee,” as in his transition team, Trump said.

That organization’s event at Mar-a-Lago drew about 20 percent more people than in past years and raised an extra $6,000 or $7,000, said its chairman, Douglas Evans. Evans said he was not sure how much more the group paid Mar-a-Lago.

Several events touted their own Trump-size theatrics. A Salvation Army gala featured an in-pool performance by a synchronized-swim team, the Palm Beach Daily News reported. A Navy SEAL Foundation benefit showcased a military simulation near the club’s pristine palms, during which seemingly armed troops in armored vehicles took down faux terrorists driving a car with “Wee Khill You” scrawled on the side, according to the Daily News. Officials from those groups did not respond to requests for comment.

But no spectacle compares to the presidential-style upgrades that have transformed the club into a high-security fortress, with metal detectors, patrol dogs and Secret Service agents on alert.

A rear exterior view of Donald Trump’s Palm Beach island home at Mar-a-Lago in December 2005. (Damon Higgins/The Palm Beach Post)

“It’s tremendous energy there. Tremendous energy,” said Lois Pope, whose foundation hosted its “Lady in Red” gala at the club in December. “My daughter said, ‘Mom, it’s surreal. There’s the president, sitting two tables away.’ ”

Many of the upper-crust events seemed to clash with the populist sales pitches Trump delivered to middle-class supporters on the campaign trail. On Jan. 12, Mar-a-Lago hosted a $1,000-a-person, invitation-only wine auction. The event was hosted by the Raymond F. Kravis Center for the Performing Arts, named for the father of Henry Kravis, the private-equity billionaire and buyout artist chronicled in the book “Barbarians at the Gate.” The Kravis Center did not respond to a request for comment.

Wall Street also had a sizable presence at Trump’s club. Although the president has contended that “hedge-fund guys are getting away with murder” when it comes to taxes, his club played host to the Palm Beach Hedge Fund Association and a Distressed Investing Summit within three days of each other in March. An invitation to the summit described Mar-a-Lago as “one of the most highly regarded private lairs in the world.” Neither the summit’s organizers nor the hedge-fund association responded to requests for comment.

And while Trump as a candidate argued that low-wage overseas labor was undermining the U.S. workforce, saying that “our jobs are being stolen like candy from a baby,” Mar-a-Lago seeks foreign workers to fill many jobs serving the needs of its guests, according to U.S. Department of Labor data. Records show that the Trump company filed Mar-a-Lago visa applications for 15 housekeepers (starting at $10.17 an hour), 19 cooks (starting at $12.74 an hour) and 30 restaurant servers (starting at $11.13 an hour, with no tips) to work at the club through the end of this month.

Like his old campaign rallies, many of the events at Mar-a-Lago offered Trump a refuge of adulation away from the travails of governance. At the Hab-a-Hearts Luncheon, Trump entered the ballroom to a standing ovation and held court in front of a giant American flag, calling the assembled attendees “the finest group of people you’ll ever meet,” a video shows. “He’s the best!” a woman screamed as Secret Service agents swept the president and his red “USA” hat through the door.

Before the election, Philips, the Palm Beach Habilitation Center’s president, said she would consider the potential social fallout before booking the club again. But after Trump won, she reaffirmed her group’s connection to what she called Palm Beach’s best venue. The group is planning to host another big event at Mar-a-Lago next spring.

The charity Hearing the Ovarian Cancer Whisper did not get a visit from Trump himself. But it still did well. Its event brought in $425,000 that day, up from $371,000 last year, according to McGrath, the group’s executive director. Meanwhile, McGrath said, the charity paid Mar-a-Lago about $60,000 to hold the lunch, up from $45,000.

“I got a lot of people coming in from Miami, which I hadn’t in the past, and I think they just kind of wanted to see what Mar-a-Lago was all about, and with this being the president’s winter home,” McGrath said. Miami is more than an hour south.

Next year, though, the group has higher hopes that Trump will appear. This year’s lunch was on a Thursday. For next year, it has reserved a Friday, a more convenient day for guests but one that comes with the bonus that Trump is more likely to be in town.

Next year, “if Trump is coming in Friday afternoon, I would guarantee he’s going to pop in,” McGrath said. “I mean, he’s just upstairs.”