That’s what this report says (via Say Anything):

The Obama-sponsored bill (SB 2386) enlarged the state’s 1961 law by shielding the person who was attacked from being sued in civil court by perpetrators or their estates when a “stand your ground” defense is used in protecting his or her person, dwelling or other property.

The bill unanimously passed the Democrat-controlled Illinois Senate on March 25, 2004 with only one comment, and passed the Democrat-controlled Illinois House in May 2004 with only two votes in opposition. Then-Governor Rod Blagojevich (D) signed it into law.