CHICAGO >> Two Chicago universities competing to host President Barack Obama’s presidential library are scrambling to address major concerns raised by the foundation picking the future site, with Chicago’s mayor stepping in to ensure his city stays competitive.

The Barack Obama Foundation, formed by longtime Obama associates, is screening two proposals from Chicago and one each from Honolulu and New York. But Chicago’s two bids, submitted earlier this month, set off red flags for the foundation’s board over land control and university leadership, according to a person close to the foundation.

The University of Chicago, a private school near Obama’s South Side home, has long been perceived as a front-runner due to its close ties to the Obamas. But the three sites the university has proposed are on Chicago Park District land, and the university can’t prove it could secure the land if it was selected, the person said.

Chicago’s other proposal, from the public University of Illinois at Chicago, raised questions about how changes in leadership will affect the school’s future, the person said. The campus and University of Illinois system are expected to have a new president, chancellor and board chairman within the next year. The person wasn’t authorized to comment publicly and demanded anonymity.

It was unclear whether either school’s bid was in serious jeopardy or whether, by drawing attention to the issues now, the foundation hoped to spur the universities to act quickly to improve their proposals.

The city of Chicago confirmed that the foundation has raised concerns about the University of Chicago bid. Mayor Rahm Emanuel, Obama’s former chief of staff, has been a vocal proponent for the city’s bids, but putting it on park land would require the park district’s sign-off.

"The mayor is committed to bringing the library home to Chicago, and we continue to work with the foundation to ensure all Chicago bids remain competitive," said David Spielfogel, the mayor’s senior adviser.

Although the park district’s board president, Bryan Traubert, is married to Obama’s longtime friend and Commerce Secretary Penny Pritzker, Traubert has recused himself. Other attempts to build on park land have drawn consternation from groups like Friends of the Parks. The group sued to block "Star Wars" creator George Lucas from building a museum on park acreage.

One potential option could be for city to acquire the land from the park district if Chicago is picked for the library. The city could return the property to the park system if another bid is selected. Spielfogel said all options were being considered but that Emanuel will "only consider potential sites that ensure park land remains under public control and that the surrounding communities have a say in the process."

The University of Chicago and the University of Illinois didn’t immediately respond to requests for comment. The University of Hawaii and Columbia University, the other two schools in contention, both have secured attractive real estate that could house the library.