(CNN) Donald Trump appeared at a fundraising event for an outside group that can collect unlimited contributions from secret donors, a move in sharp contrast with his public calls for transparency in money and politics.
Trump attended a fundraising event Sunday at the home of real estate developer Charles Kushner and his wife, Seryl -- Ivanka Trump's in-laws -- on the Jersey Shore. Some attendees were asked to pony up $10,000 for a group called Make America Great Again. According to an invitation, organizers have set up a super PAC as well as a 501(c)(4) nonprofit. While a super PAC is required to disclose its donors, the nonprofit is not.
Donors were given the option of making contributions to the super PAC or to the nonprofit entity, noting their personal information would be kept private if they chose to contribute to the nonprofit, according to an invitation to the event.
Trump "attended as a guest and did not solicit donations from any of the attendees," said campaign spokeswoman Hope Hicks. "He is self-funding the campaign."
But there are increasing signs Trump's allies are ramping up their fundraising efforts to build a war chest for a longer than expected campaign. In addition to the New Jersey event, Trump made an appearance at an event hosted by the super PAC in Manhattan last month, a campaign aide confirmed. On Friday, he is scheduled to attend an event in Massachusetts that the host is billing as a fundraiser.
The apparent shift in Trump's fundraising strategy hasn't altered his rhetoric on the stump very much.
Donald Trump: Macho Man of 2016
Trump has touted his personal wealth as a credential on the campaign trail, bragging that he doesn't need donations from anyone and calling for an overhaul of the campaign finance system.
Trump gave a hint Sunday that he may be changing his tone, saying, "Certainly I would take contributions, I actually like the idea of investing in a campaign."
"But it has to be no strings attached. I don't want any strings attached," he said on CBS' "Face The Nation."
But on Tuesday evening -- just days after appearing at the New Jersey fundraiser -- Trump railed against the lack of transparency in the system and lamented how difficult it is to identify donors who make big contributions to organizations supporting presidential candidates.
"I think the most important thing is transparency," Trump told reporters. "You need to know who's putting up what so when they start making deals in a year or two years or three years, you know what's happening."
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At a campaign stop Tuesday in Dubuque, Iowa, Trump floated the idea of accepting more donations. He said numerous people have offered to write his campaign checks for millions of dollars.
"I turn down so much money. I feel like such a stupid person," Trump said. "I'll just take a vote. How about if I take all of this money -- and I promise you, I swear to you -- that I won't do anything for these people. How about that?"
As the packed ballroom broke out in a chorus of "boos," Trump renewed his pledge that he would not be beholden to donors and their special interests.
"I think one of the things they like about me is nobody's going to buy me," Trump said.
Donald Trump's rise
President-elect Donald Trump has been in the spotlight for years. From developing real estate and producing and starring in TV shows, he became a celebrity long before winning the White House.
Trump at age 4. He was born in 1946 to Fred and Mary Trump in New York City. His father was a real estate developer.
Trump, left, in a family photo. He was the second-youngest of five children.
Trump, center, stands at attention during his senior year at the New York Military Academy in 1964.
Trump, center, wears a baseball uniform at the New York Military Academy in 1964. After he graduated from the boarding school, he went to college. He started at Fordham University before transferring and later graduating from the Wharton School, the University of Pennsylvania's business school.
Trump stands with Alfred Eisenpreis, New York's economic development administrator, in 1976 while they look at a sketch of a new 1,400-room renovation project of the Commodore Hotel. After graduating college in 1968, Trump worked with his father on developments in Queens and Brooklyn before purchasing or building multiple properties in New York and Atlantic City, New Jersey. Those properties included Trump Tower in New York and Trump Plaza and multiple casinos in Atlantic City.
Trump attends an event to mark the start of construction of the New York Convention Center in 1979.
Trump wears a hard hat at the Trump Tower construction site in New York in 1980.
Trump was married to Ivana Zelnicek Trump from 1977 to 1990, when they divorced. They had three children together: Donald Jr., Ivanka and Eric.
The Trump family, circa 1986.
Trump uses his personal helicopter to get around New York in 1987.
Trump stands in the atrium of the Trump Tower.
Trump attends the opening of his new Atlantic City casino, the Taj Mahal, in 1989.
Trump signs his second book, "Trump: Surviving at the Top," in 1990. Trump
has published at least 16 other books, including "The Art of the Deal" and "The America We Deserve."
Trump and singer Michael Jackson pose for a photo before traveling to visit Ryan White, a young child with AIDS, in 1990.
Trump dips his second wife, Marla Maples, after the couple married in a private ceremony in New York in December 1993. The couple divorced in 1999 and had one daughter together, Tiffany.
Trump putts a golf ball in his New York office in 1998.
An advertisement for the television show "The Apprentice" hangs at Trump Tower in 2004. The show launched in January of that year. In January 2008, the show returned as "Celebrity Apprentice."
A 12-inch talking Trump doll is on display at a toy store in New York in September 2004.
Trump attends a news conference in 2005 that announced the establishment of Trump University. From 2005 until it closed in 2010, Trump University had about 10,000 people sign up for a program that promised success in real estate.
Three separate lawsuits -- two class-action suits filed in California and one filed by New York's attorney general -- argued that the program was mired in fraud and deception. Trump's camp rejected the suits' claims as "baseless." And Trump has charged that the New York case against him is politically motivated.
Trump attends the U.S. Open tennis tournament with his third wife, Melania Knauss-Trump, and their son, Barron, in 2006. Trump and Knauss married in 2005.
Trump wrestles with "Stone Cold" Steve Austin at WrestleMania in 2007. Trump has close ties with the WWE and its CEO, Vince McMahon.
For "The Apprentice," Trump was honored with a star on the Hollywood Walk of Fame in January 2007.
Trump appears on the set of "The Celebrity Apprentice" with two of his children -- Donald Jr. and Ivanka -- in 2009.
Trump poses with Miss Universe contestants in 2011. Trump had been executive producer of the Miss Universe, Miss USA and Miss Teen USA pageants since 1996.
In 2012, Trump announces his endorsement of Republican presidential candidate Mitt Romney.
Trump speaks in Sarasota, Florida, after accepting the Statesman of the Year Award at the Sarasota GOP dinner in August 2012. It was shortly before the Republican National Convention in nearby Tampa.
Trump appears on stage with singer Nick Jonas and television personality Giuliana Rancic during the 2013 Miss USA pageant.
Trump -- flanked by U.S. Sens. Marco Rubio, left, and Ted Cruz -- speaks during a CNN debate in Miami on March 10. Trump dominated the GOP primaries and emerged as the presumptive nominee in May.
The Trump family poses for a photo in New York in April.
Trump speaks during a campaign event in Evansville, Indiana, on April 28. After Trump won the Indiana primary, his last two competitors dropped out of the GOP race.
Trump delivers a speech at the Republican National Convention in July, accepting the party's nomination for President. "I have had a truly great life in business," he said. "But now, my sole and exclusive mission is to go to work for our country -- to go to work for you. It's time to deliver a victory for the American people."
Trump apologizes in a video, posted to his Twitter account in October, for vulgar and sexually aggressive remarks he made a decade ago regarding women. "I said it, I was wrong and I apologize,"
Trump said, referring to lewd comments he made during a previously unaired taping of "Access Hollywood." Multiple Republican leaders rescinded their endorsements of Trump after the footage was released.
Trump walks on stage with his family after he was declared the election winner on November 9. "Ours was not a campaign, but rather, an incredible and great movement," he told his supporters in New York.
Trump is joined by his family as he is sworn in as President on January 20.
And yet, some guests said they attended Trump's weekend fundraiser and donated -- begrudgingly -- because they did not want to jeopardize their business relationships with the Kushners or the Trumps, according to an attendee. Both families are powerful forces in the real estate industry and the Kushners have already thrown their support behind Trump's campaign. Seryl Kushner donated $100,000 to the super PAC supporting him, according to a source close to the family.
The person close to the Kushner family disputed the notion that the New Jersey event was arranged as a fundraiser and denied that there was "pro-active solicitation," saying guests only received information about the outside spending group if they requested it. A representative for the nonprofit group and super PAC declined to comment.
On Friday, Trump will head to Massachusetts for an event that the host is branding as a fundraiser but the campaign is insisting is not.
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Ernie Boch Jr., the chief executive of Boch Automotive Enterprises and the host of Friday's event, said he had received at least 700 RSVPs from friends and acquaintances. He said the campaign plans to charge $100 per person.
"I've always been a Trump fan since the '80s," Boch said. "He's a hero to most business guys."
Meanwhile, Trump and his campaign said they had no plans to collect donations from the event.
"It's just a very small situation, and I don't consider it a fundraiser," Trump said. "In fact, people don't have to pay."
Trump's campaign spokeswoman said they would only use the donations to cover the cost of the event, such as food and beverages. Boston chef Tony Ambrose is expected to cater the event, while Massachusetts cover band Fortune will supply the entertainment.
Boch initially reached out to the campaign in the hopes of planning a more intimate affair with a higher price tag. However, Trump's campaign lobbied for a larger gathering, he said.
Boch said the event is "a chance for me to get up close" to the candidate, but added that he's not expecting any favors in return.
As for whether he has any reservations about helping a billionaire candidate raise funds, Boch said, "You can never have enough money."
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