The group supporting an expanded smoking ban that's on South Dakota's ballot says it would protect workers and reduce some health care costs.

The Legislature in 2009 voted to ban smoking in bars, video lottery establishments and Deadwood casinos. Owners of bars and casinos circulated petitions to refer it to the ballot this fall as Referred Law 12.

The "Yes on 12" group launched its campaign Tuesday by emphasizing the dangers of secondhand smoke to workers in bars and casinos, and to the public in general.

The opposing group, Citizens for Individual Freedom, says a ban infringes on the rights of business owners and could reduce state revenue if people stop gambling because they can't smoke while playing video lottery.