The staffer, William Norels, was a part-time consultant. In 1998, he was accused of misappropriating $100,000.
"He set up events for us. He wasn't a major employee of our campaign, and as soon as we found out about it ,we let him go. It was just unfortunate that it happened, and we owned up to it," Comptroller Dan Hynes said.
"That person took money from the taxpayers of Illinois, about $100,000, and that was money designed to create jobs and economic growth, especially in the inner city," incumbent Gov. Pat Quinn said.
U.S. Senate candidate and state treasurer Alexi Giannoulias and Cook County Board president candidate Toni Preckwinkle also were among those who took part in Sunday's forum.