Father Michael Pfleger of Saint Sabina Church and other community leaders announced the creation of the Stop Concealed Carry Coalition. They say they have gathered 6,500 signatures from people who oppose the bill.
The group hopes Illinois lawmakers will not try to pass the law when they convene later this week.
The National Rifle Association and other gun-industry groups are lobbying to get the law passed as soon as possible. Illinois is the only state that does not have a concealed-carry law.