Former President Bill Clinton, his wife, former secretary of state Hillary Clinton, left, and their daughter Chelsea Clinton speak to guests at the Clinton Global Initiative (CGI) on June 14 in Chicago. (Scott Olson/Getty Images)

The Clintons are in fundraising mode again, inviting supporters to a musical weekend in London, a “night out” in San Francisco with Hillary and Chelsea and — in a select series of private, one-on-one meetings — the opportunity to write a check for $5 million to $10 million.

The invitations, delivered by phone and e-mail, resemble those of past political campaigns, complete with tiered levels and special access that depends on the size of the contribution.

But this current quest for cash, which shifts into high gear this fall, is not to fund a run for political office. It is to boost the financial standing of the newly rechristened Bill, Hillary and Chelsea Clinton Foundation.

As he contemplates his legacy, former president Bill Clinton is trying to build an endowment with the declared goal of $200 million to $250 million to ensure that the charitable foundation he started lives on after his death.

The foundation’s causes are expanding from those championed by the former president — fighting AIDS, climate change and global poverty — to include newer domestic priorities embraced by wife Hillary and daughter Chelsea. And that expansion means more fundraising.

“We had to have another way to raise the funds that we need in order to keep the lights on,” said Bruce R. Lindsey, chairman of the foundation, speaking on behalf of the Clintons. “You cannot continue to rely upon a single individual to raise all the money you need to raise on a yearly basis. First of all, it is unbelievably grueling on President Clinton, and second of all, if anything were to happen to him it would end.”

While this fundraising push is philanthropic in nature, there are political implications. There is an unspoken deadline, for example. Clinton insiders said they hope the endowment drive will be completed ahead of the 2016 presidential campaign so that if Hillary Clinton chooses to run, the foundation fundraising would not distract from her campaign.

“It’s the optics of it — it would be horrible,” said one Clinton Foundation fundraiser who requested anonymity because he was not authorized to discuss the foundation’s strategy. “They just want to get it done to give her the option so if she wants to run, the foundation is taken care of.”

As the former secretary of state broadens her public profile with a series of major policy addresses, the Clinton Foundation has become the command post for all things Hillary. She is building a staff at its New York headquarters and launching programs on early childhood development and women’s and girls’ empowerment.

But some allies already see signs that the newly reorganized charity is a “pre-campaign organization,” helping enhance Clinton’s reputation and expand her network of supporters.

“People are tripping over themselves to contribute to the foundation now,” said one Clinton ally, who spoke only on the condition of anonymity because of the sensitivity of the topic. “It’s a way for political supporters to help Hillary at a time when there is no campaign to contribute to.”

The action in Clintonland

Bill Clinton is not the first former president to build an endowment for his foundation, a common practice for non-profit organizations. Jimmy Carter has been raising money for years to endow the Carter Center, which focuses on peace and health care.

The amount the Clinton Foundation is seeking to raise is small compared with giant philanthropies; the Bill and Melinda Gates Foundation, for instance, has an endowment of about $37 billion.

Still, the ability to spend millions annually in pursuit of targeted good causes is something any politician would envy. And the pre-campaign aura around Hillary Clinton is driving more money and attention to the foundation.

“Are people saying, ‘Listen, get in line for Hillary for President by raising money for the foundation?’ ” the foundation fundraiser said. “You don’t hear anybody saying that. It’s almost implicit. If you want to be in the action, go where the action is. And right now, the action in Clintonland is at the foundation.”

A second foundation fundraiser said: “There are people who give to the foundation to cozy up to Hillary Clinton. Anybody who tells you that doesn’t happen is full of [crap].”

But Lindsey said he believes the foundation’s charitable projects should be reward enough to make donations. “I frankly don’t have a clue what the motives are of the people who support the Clinton Foundation,” he said. “I’m just grateful for their support. The work we do is important.”

The Clintons held a fundraiser Friday at celebrity chef Tom Colicchio’s Topping Rose House in Bridgehampton, N.Y., near their rented beach house, and have another planned on Sept. 9 in Washington. For $1,000 a person, guests can attend a cocktail reception at the Italian Embassy. And for $25,000 a couple, they get dinner with the Clintons at their residence across the street.

In San Francisco on Nov. 9, Hillary and Chelsea Clinton will host a “Millennium Network” event aimed at cultivating a younger generation of philanthropists. According to an invitation, there are six tiers of donations, ranging from $150 for individuals to $15,000 for a couple seeking a photograph with Hillary Clinton.

“It’s very smart of her to do something so accessible,” said Wade Randlett, one of President Obama’s top Silicon Valley fundraisers. “Out here, both big donors and small ones are uncomfortable with anything that smacks of ‘elites.’ ”

This fall’s events, including the London concert weekend with all three Clintons on Oct. 11-12, raise money for annual operations, foundation officials said. Endowment-focused events will not begin for several months.

The Clintons personally have begun intensive outreach to elite donors, seeking individual gifts of $5 million to $10 million, one official said. They soon will broaden their appeal to those who might give lesser amounts, perhaps $500,000 to $1 million.

Officials declined to identify these donors or say how much they might have pledged. But likely endowment funders include Canadian mining executive Frank Giustra and Chicago businessman Fred Eychaner, who have given more than $25 million each to the foundation, as well as film producer Stephen L. Bing and entertainment executive Haim Saban, whose gifts have ranged between $10 million and $25 million each.

Pierre Omidyar, the billionaire founder of eBay, said he was approached this year about the endowment drive. “I wish them much success,” he said. Omidyar gave $1 million to the foundation several years ago to support its work on AIDS in Africa. “The Clintons set an inspiring example of finding smart, innovative and high-impact ways of continuing to serve even after leaving public service,” he said.

Political skirmishing

Hillary Clinton’s new foundation role has obvious political benefits. She can engage influential leaders across various industries and activist constituencies with an ambitious agenda of good works and nonpartisan causes.

It also allows her and her husband to raise unlimited funds, free of the limitations and disclosure requirements under campaign finance laws. Lindsey said the foundation likely would continue to publicly disclose its donors annually, something it agreed to do when Clinton became secretary of state in 2009.

Michael Meehan, an adviser to former senator John F. Kerry during the Democrat’s 2004 presidential campaign, said the foundation is “an ideal place” for Clinton to be while contemplating a run. “The foundation provides the advantages of incumbency without the downsides,” he said.

Despite the fact that the endowment campaign has been launched while no Clintons are serving in public office, it has been difficult to avoid political skirmishing. Hillary Clinton’s new perch at the foundation already has revealed potential downsides. Critics have questioned whether former aides to both Clintons may have benefited financially based on their association with the family.

When the Clinton Global Initiative met in Chicago in June, Terry McAuliffe, a longtime Clinton intimate who sits on the foundation’s board and is the Democratic nominee for governor of Virginia, organized a gubernatorial fundraising event nearby that featured Bill Clinton and CGI attendees.

Suggestions of back-scratching and a lack of financial discipline at the Clinton Foundation has produced some scrutiny recently, including a New York Times story that described efforts by Chelsea Clinton to introduce more rigorous fiscal management.

Bill Clinton subsequently defended his foundation, which has been professionalizing its operations as well as its fundraising strategy, led by development director Dennis Cheng.

Enemies became allies

The scrutiny is sure to continue as long as Hillary Clinton remains a potential presidential candidate. Some major donors cautioned against any blurring of the lines between the foundation’s nonprofit work and Clinton’s political aspirations.

“The two have to be carefully separated,” said Lewis B. Cullman, a businessman and philanthropist who has given more than $500,000 to the foundation. “If Hillary’s going to use the foundation as an entree to raising money for her campaign, I don’t think that would be very good.”

The argument that the Clinton Foundation’s work transcends politics is made by some one-time Clinton political enemies who are now boosters of the charitable organization. The prime example may be Christopher W. Ruddy, founder of the conservative Web site NewsMax, who in the 1990s promoted a conspiracy theory about the death of former Clinton White House adviser Vince Foster.

Since then, Ruddy has given more than $500,000 to the Clinton Foundation. He traveled with the former president to Africa last year and, in an interview, hailed Clinton’s work as “good for the world and for America.”

Another conservative, William F. Austin, said he “couldn’t imagine voting for Hillary.” But the founder and chief executive of a major hearing aid manufacturer, whose nonprofit foundation distributes hearing devices in third-world countries, has given between $250,000 and $500,000 to the Clinton Foundation. He said he is in talks to be a significant funder of the endowment.

“When I met Bill Clinton, the first thing he did was challenge me to do more,” Austin said. “I said, ‘I’m flat out; I’m using all my time,’ and without blinking he said that wasn’t good enough and I had to find a way to leverage myself.”

Alice Crites contributed to this report.