State Question 788 would make it legal to grow, sell, and use marijuana for medical purposes, and would give doctors a lot of leeway in determining what conditions qualify for a medical marijuana prescription. Activists started working on getting the question on the ballot more than two years ago with a signature drive. If passed, the law would allow those in possession of a license to have up to eight ounces of marijuana, six mature plants, six seedlings, and edibles or concentrated forms of the drug.

But the question itself has sparked opposition from law enforcement, business, and faith and political leaders because of how few restrictions it places on qualifying for medical marijuana. They equate it to a plan to legalize recreational use and have spent $500,000 on a media campaign urging voters to say no.

Although Oklahoma is conservative on most issues, attitudes to marijuana are shifting. Even some staunch, traditional Republicans are changing their minds and supporting the campaign for medical marijuana, as PBS reports.

And polling by SoonerPoll in May showed 57.5% of Oklahoma voters favoring the medical marijuana measure, compared to 29.6% who opposed it.

The vote comes two years after the traditionally tough-on-crime state reduced the severity of all drug possession crimes to misdemeanors. That measure also faced opposition from law enforcement, but voters supported it anyway.

Voters in Michigan and Utah will also consider ballot measures on marijuana later this year. Utah’s measure would legalize medical marijuana while Michigan’s would legalize recreational use of the drug.