The Chateaux at Silver Lake, at Deer Valley Resort in Park City, Utah, is seen as attendees of Republican presidential candidate Mitt Romney register for a private donors conference Friday, June 22. (Charles Dharapak/AP)

— If Mitt Romney’s presidential campaign were listed on the stock market, then those populating Utah’s luxurious Deer Valley resort this weekend were its biggest shareholders. They showed off silver lapel pins signifying their elite status, carried around custom Vineyard Vines canvas totes and exuded collective amazement after watching Olympic ski jumpers do flips into a giant swimming pool.

But mostly they were here to take stock of their investment, Romney. And after two days of intimate mingling with the presumptive Republican nominee and his senior advisers at a rarefied retreat in Park City, they have grown bullish, saying they taste victory like never before in Romney’s six-year quest for the presidency.

“The tide is turning in Mitt’s favor,” said Bobbie Kilberg, a top fundraiser from Virginia. “There’s a real sense here that he can win, and it’s not just that people are being Pollyannaish. You can feel it in the air. . . .This place is full of kinetic energy.”

This weekend’s “Romney Victory Leadership Retreat” marked both the culmination of Romney’s intense and relentless personal cultivation of political benefactors and an official coming-together of GOP forces after a bruising primary season.

Romney’s wealthy supporters called the retreat the second-most important event on the summer calendar, behind the Republican National Convention in Tampa. Romney’s high command decamped here from Boston to rub elbows with top-flight donors, including the normally reclusive campaign manager Matt Rhoades and senior adviser Beth Myers, who is leading Romney’s confidential vice presidential search.

The roughly 800 guests, who each contributed $50,000 or raised at least $100,000 for the campaign, reveled in unfettered access not only to Romney and his family — Ann Romney gathered the women guests for an afternoon tea — but also to many Republicans who could play important roles in his administration.

Among them were a handful of vice presidential prospects, including Sen. John Thune (S.D.), who shared pizza and posed for pictures with donors at a hotel bar Friday night, as well as Rep. Paul Ryan (Wis.) and former Minnesota governor Tim Pawlenty.

There were other Republican luminaries here as well, including Karl Rove, who runs the super PAC American Crossroads and held court at the five-diamond Stein Eriksen Lodge, and Sen. John McCain (Ariz.), the party’s 2008 nominee.

Former secretary of state Condoleezza Rice delivered a 15-minute luncheon speech on foreign and domestic policy Saturday that donors described as electrifying and had attendees on their feet twice. One donor said Rice was “the star of the show,” while another said that, if it was a vice presidential tryout, “she hit it out of the park.”

The retreat, said Peter A. Wish, a Florida doctor, was “a combination of celebrating and cheering along with meeting with people who potentially could have a big impact in the administration.” Wish enjoyed lunch Friday on a sun-drenched patio alone with Michael Chertoff, a Romney adviser and former secretary of Homeland Security.

The donors — many of whom are what Wish called “sales people,” raising money from friends and associates — received private briefings from Rhoades, Myers, chief strategist Stuart Stevens and message guru Eric Fehrnstrom.

More than a dozen senior campaign aides were on site, detailing the daily rhythms at Boston headquarters and their strategies in battleground states as well as enlisting some donors to serve on expanded policy advisory committees. Some bundlers said finance chairman Spencer Zwick urged them to double their totals to achieve fundraising parity with President Obama.

“A lot of people will go home and call a bunch of their friends and raise more money,” said David Beightol, a Washington lobbyist and Romney fundraiser.

The retreat, which was closed entirely to the press, highlighted the degree to which Romney relies on deep-pocketed bundlers, whom his campaign has declined to identify. During the primaries, his campaign has raised 60 percent of its money from people who gave the maximum legal amount of $2,500, according to the Campaign Finance Institute.

Some of the donors here underscored the extraordinary wealth behind the Romney campaign. Malcolm Pray, a fundraiser from Greenwich, Conn., pulled from his blazer pocket a piece of paper with color thumbnails of 50 vintage cars in his personal collection, studded with such models as a 1957 Porsche and a 1961 Ferrari. He showed reporters a booklet summarizing his charitable work for poor children with tips on “How to Become a Millionaire,” such as “be patriotic,” “stay away from drugs and liquor” and “slobs do not become millionaires.”

This is the first large-scale retreat bringing together the extended Romney team. Campaign staff said they initially expected 400 supporters to attend, but double that turned out.

Several longtime Republican benefactors said this weekend’s festivities were more ambitious than any they had experienced, including President George W. Bush’s retreats at his Texas ranch.

“This is much more thorough. This is much more extensive,” said Brenda LaGrange Johnson, a former ambassador to Jamaica. “The Crawford events were speeches and barbecues.. . . This is a working retreat.”

“We get a lot of one-on-one time with Mitt,” she added. “I met him in 1994, and 20 minutes after meeting him, I said, ‘Mitt, you’re going to be president of the United States, and I’m going to help you.’ I just felt the spark.”

Among the special guests here was Bill Kristol, the conservative commentator who through the primaries penned sometimes scathing critiques of Romney. By speaking here, though, he effectively was dropping his arms. As Kristol arrived at the Chateaux at Silver Lake, he set down his suitcase, took in the mountainside views and exulted, “It’s not really work.”

For Romney, however, the weekend was work indeed, as he zipped around this mountain oasis in his Secret Service motorcade. Donors said he was noticeably relaxed, projecting confidence and seeming at ease as he strategized with his state finance chairmen, attended policy seminars on issues ranging from energy to banking to Israel and toasted the fundraising team at a Friday night cookout at Utah Olympic Park, near the bobsled track and alpine ski jumps.

At the cookout, his wife, Ann, introduced four of their sons (the fifth, Ben, is a medical resident in radiology and was on call). Then, as the sun set against the sweeping expanse of the Wasatch Range, Romney delivered a version of his stump speech. Donors checked out Olympic medals, figure skating costumes and other memorabilia from the 2002 Winter Games, which Romney led.

Beneath a canopy tent lit by chandeliers and ornamented with bouquets of sunflowers, Romney mingled with donors over plates barbecued beef, salmon and potatoes au-gratin. And at 7 p.m., Olympic ski jumpers put on a show, skiing down twin tracks and doing flips into a swimming pool, the water bubbling seconds ahead to soften their landings.

Then Romney retired to his room at the St. Regis, where he spent time with extended family members. One of the candidate’s nieces, Kristen Romney Hubbs , presented him a huge oil painting she made of Romney’s face infused with an American flag bearing the slogan, “American Strong.” She said the flag draws out her uncle’s “emotional energy.”

Romney’s older brother, Scott, roamed the retreat grounds sporting a puffy black Patagonia winter jacket embroidered with the logo of Solamere Capital, the private equity firm started by Mitt Romney’s eldest son, Tagg, and Zwick. Scott Romney’s ex-wife, Ronna, was here, too, chatting with donors and reporters about her still-close relationship with Ann Romney.

Romney donors came here from coast to coast, some by private jet, but their common thread was business. Over and over again, they said, they feel a kinship with Romney, himself an M.B.A. who founded and ran the corporate buyout firm Bain Capital.

One fundraiser joked that tiny Heber City Municipal Airport nearby “looked like an Air Force base.”

Travis B. Hawkes, an Idaho entrepreneur and venture capitalist who owns sports apparel stores, said Romney, unlike past presidents, “knows what it’s like to lay awake at night worrying about your cash flow and meeting payroll.”

Many donors here said they had a personal stake in Romney’s campaign. For Al Montna, a rice farmer from Yuba City, Calif., it’s Romney’s pledge to loosen or repeal a menu of Obama-era environmental regulations. “U.S. business is being regulated out of business,” Montna said. “Business is looking for leadership, and that’s Mitt.”