The ballot initiative that would have allowed instant horse racing gambling machines failed in Idaho.

The initiative, Proposition 1, received enough signatures in July to be on the Nov. 6 ballot. It generated millions of dollars in campaign spending from both sides of the issue and attracted high-profile endorsements, including from Gov. Butch Otter, who said he hoped it would rejuvenate Idaho’s “diminished” live horse racing industry.

If it had been approved, Idaho race tracks with live or simulcast racing would have been able to use the machines, which generate revenue to make purses more attractive to jockeys.

Opponents to the initiative said allowing the machines was basically legalizing non-reservation gambling by another name.

Historical horse racing terminals include a tiny screen that shows a few seconds of the end of a randomly selected past horse race, as reels spin, bells ring, and bettors win or lose. The machines also are called “instant racing” machines and have helped other states revitalize their horse racetracks.

The Idaho Legislature briefly allowed the use of the machines before banning them in 2015 after seeing their similarity to slot machines. Les Bois Park, formerly Idaho’s largest horse-racing venue, shuttered after that.