Rosen allegedly worked out of Paul's Stan Lee Media office as he oversaw preparations for the star-studded event. Witnesses say he refused to keep records on vast amounts of cash spent on Mrs. Clinton's behalf.

But Paul's testimony could spell just as much trouble for Mrs. Clinton, the Democratic Party's likely 2008 presidential nominee.

Before meeting with U.S. District Judge Leonard D. Wexler, Paul told the New York Sun that he was eager to testify against Mr. Rosen at trial, and potentially against Mr. and Mrs. Clinton.

"I have come to take responsibility for my actions and put myself at the mercy of the court. Senator Clinton has not," he declared.

Mr. Paul told the Fox News Channel last year that he personally apprised Mrs. Clinton of the money being spent on her behalf.

Fund-raiser Aaron Tonken, who helped Paul produce the August 2000 event, has given prosecutors a similar account - and both have reams of financial records to back their stories.

David Rosen is set to go on trial in Los Angeles on May 3.

Editor's note: