Opponents of an Ohio law that effectively bans storefront sweepstakes parlors can start collecting signatures in their effort to have voters repeal the measure next year. State officials today certified an initial 1,000 signatures and petition summary from the group called the Committee to Protect Ohio Jobs. That means it can begin gathering more than 231,000 signatures needed to place a referendum on the ballot. The group wants the law repealed to force legislators to pass a new law regulating the industry and shut down what it calls rogue sweepstakes parlor operators. It has until Sept. 3 to collect the required signatures. More than 620 Internet cafes operate in Ohio, representing competition to legalized casinos and charity games. The law's supporters say Internet cafes were harboring illegal gambling.