Called "Individual H" in the indictment, Cherry allegedly was to receive a fee for a fraudulent investment deal cooked up by Rezko, even though he did no work.
Cherry is not charged with any crime and is cooperating with investigators. He has publicly denied doing anything wrong. His connection to Rezko could be problematic for Clinton, as her chief rival, Obama, has been dogged throughout his presidential campaign by questions about his relationship with Rezko.
Clinton campaign spokesman Phil Singer declined to comment.
David Donnelly, a spokesman for Public Campaign, which advocates public financing of political campaigns, said the pace of fundraising made it almost impossible to identify every donor with professional connections that could be potentially embarrassing to the candidate.
"I don't think there is any screen that could weed out questionable money and run a competitive race for president," Donnelly said. "The entire campaign finance system puts candidates in a compromising situation in city after city."
A real estate developer and prodigious fundraiser for Democrats, Rezko has contributed thousands of dollars to Obama's campaigns throughout his political career and raised thousands more. Their relationship came under scrutiny after Rezko was indicted last October on charges of trying to extort money from management firms hoping to do business with the $39 billion Illinois Teachers Retirement Fund.
Rezko's legal problems have been a source of embarrassment for Obama, who has tried to convince voters he is a different kind of politician — one not prone to scandals involving shady donors. The Obama campaign has donated about $37,000 in Rezko-related money to charity, and a spokesman said Obama hasn't been in contact with his former supporter for some time.
Cherry has contributed more than $87,000 to Democratic candidates since 2003, including Clinton's Senate re-election campaign in New York. Active in Jewish causes, he was named to the U.S. Holocaust Memorial Council by President Clinton in 2001.
Cherry also has done legal work for International Profit Associates, a management consulting company whose executives have made contributions to Clinton's two Senate races. The firm now faces a federal sexual harassment suit filed by more than 100 female former employees, and the Illinois attorney general is looking into allegations that the firm engaged in deceptive marketing practices.
Several elected officials have returned contributions from IPA executives. Clinton has kept the donations, estimated to be nearly $130,000.