Once it was, the state medical association steered the opposition. By August, a senior official in the Church of Jesus Christ of Latter-day Saints was warning that residents of some states that had legalized marijuana were seeing serious "health and safety consequences."

But, then, something curious happened: Key opponents negotiated an agreement with the measure's backers and other state leaders. Now, no matter what happens on Election Day, state lawmakers will be called into a special legislative session and plan to enact an alternate medical marijuana program.

Unless the pact falls apart, Utah, one of the most conservative states in the country, will join the more than 30 other states that have already sanctioned some form of medical marijuana.

"There's a lot of tailwind nationally pushing this issue," said DJ Schanz, director of the Utah Patients Coalition, the group that worked to get the measure on the ballot. "A lot of states have experimented with medical cannabis and seen great results. The hysterical opposition has proven to be false."