Lura Lynn Ryan was diagnosed last week with an aggressive form of lung cancer. Her doctors say she has three to six months to live.
The Reverend Jesse Jackson is also making an appeal to President Barack Obama and Governor Pat Quinn for Ryan's release.
In his appeal, Rev. Jackson wrote, "This request is not meant as a suggestion that the crimes for which Mr. Ryan was convicted were excusable, nor meant to minimize the pain or suffering of those impacted by the actions which led to his conviction."
George Ryan has served less than half of his six-and-a-half-year sentence.
The judge in the case could hear the evidence as soon as this week.