CHICAGO – After turning over the White House next month to a successor who aims to scuttle some of his key initiatives, President Obama and his foundation will embark on an epic endeavor — racing for donors who can launch their fund drive for a presidential library and museum on Chicago's South Side.

The scale is daunting: While Obama's library planners decline to provide a cost estimate, the George W. Bush library and endowment cost more than $500 million. Adding to the pressure, the Obama project is the first to be built under sharply increased federal requirements for a sustaining endowment. Obama chose to add another hurdle by pledging not to personally raise money for the project during his time in office.

So the nonprofit Obama Foundation faces a steep climb. A wild card hovers: What will the election of Donald Trump mean for the fundraising campaign?

"The success of a really big campaign like this hinges on a small number of very large gifts at the beginning," said David Jones, who raised money for former President George H.W. Bush's library in College Station, Texas.

He is among a number of observers who think Trump's victory might help with some of the work ahead for Obama's Democratic loyalists.

"His friends know there needs to be an institution that will keep his legacy and his accomplishments very much alive," Jones said.

Obama lifted the bar for presidential campaigns, raising nearly $750 million in 2008 and $722 million in 2012.

He "is going to be leaving the presidency with [high] popularity numbers, and Michelle Obama is a rock star in her own right," said James Rutherford, local planning coordinator for the William J. Clinton Presidential Library and Museum in Little Rock.

Early money for the library project has flowed from tech executives, venture capitalists, real estate developers and foundations. While Obama remains in office, the foundation agreed not to accept contributions from for-profit entities, federal lobbyists, or foreign nationals or agents.

"We are limiting our fundraising now to a group of longtime supporters of the president and limiting the amount that they can contribute," Martin Nesbitt, chairman of the Obama Foundation, told reporters last summer. "But when the term is over, we will modify that in a way that facilitates us getting to our fundraising goals."

The Obama Presidential Center, which will include a library, museum and offices in Jackson Park on the South Side, will be the 14th presidential library in a system founded in 1939 by the National Archives and Records Administration.

The system is kept afloat by public and private money. The national archive spent $67 million in the last fiscal year on library operations and programs, with additional support coming from privately funded library endowments.

The Obama Foundation will raise private money for the center's construction and for an endowment to assist the National Archives' operation of the library and museum. The foundation must raise a sum equal to 60 percent of construction costs for the endowment it creates, up from a 20 percent requirement previously in place.