PIERRE, S.D. (AP) — A ballot measure that could give patients in South Dakota more choice of doctors within their health insurance networks has attracted more than $560,000 in spending on television ads to sway voters ahead of Election Day.

The Center for Public Integrity released an analysis of the spending on Thursday. Proponents of the "any willing provider" measure, Initiated Measure 17, have spent $267,000 on nearly 800 ads. Opponents have spent at least $294,000 airing nearly 700 spots.

The proposal asks voters to decide if doctors who agree to insurers' conditions should be able join their preferred providers, or in-network, lists.

Preferred providers usually cost patients less than those outside the network. Opponents say the plan would increase health care costs.

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