On November 8, voters in five states will not only vote to choose their next president, they will also decide if they would like to decriminalize the recreational use of cannabis. If successful, the ballot proposals would add Maine, Massachusetts, California, Nevada, and Arizona to the list of states which have effectively legalized recreational weed. As Washington, Oregon, Colorado, Alaska, and the District of Colombia already allow recreational use, the new laws would make weed legal for just under 1 in 4 Americans.

In the process, legalization efforts in the western states moved from a niche issue to the political mainstream, gaining endorsements from organized labor, and drawing the attention of large drug companies.

Out of all of the legalization proposals, California’s would likely have the greatest impact, due simply to its population. Over the course of August and September, the measure gained important endorsements from the Los Angeles Times, the Orange County Register, the San Diego Free Press, and the San Francisco Chronicle, as well as endorsements from numerous other smaller papers. Now, going into the final weeks of the campaign, several signs indicate that proposition 64 in California is poised to pass. The most recent poll, conducted October 14-23, showed 55 percent support of the measure among likely voters. (The poll had a margin of error of 4.6 percent).

Another sign of the measure’s strong support base is its donations. The campaign supporting the measure has raised more than $18 million, compared to the $2 million raised by opponents of the proposal.

The well-funded proposal has received more than half of its money from a mere handful of private donors and groups, who are spending large sums in an attempt to influence the outcome in California. Tech-billionaire Sean Parker and his affiliates have provided roughly 47 percent of the legalization campaign’s total contributions on their own, some $8.6 million. The second-largest donor is George Soros’s Fund for Policy Reform. And Henry Van Ameringen, an out-of-state philanthropist, has donated an addition $1 million.

Over 90 percent of the money raised to support the proposition comes from Parker, Van Ameringen, the Fund for Policy Reform, and two other donors.

But perhaps more significant than the sums given is the coalition that has formed to support the measure. Although Proposition 64 has received the support of stars like Jay Z, Olivia Wilde, and Danny Glover, it will likely benefit more from mainstream endorsements, like that of the National Latino Officers Association, the United Farm Workers, and the California Nurses Association.

These labor groups demonstrate the growing normalization of marijuana use, which has now won coveted union endorsements.

The picture looks similar across the border in Nevada, where voters will vote on Question 2. This proposal would legalize recreational use of marijuana by those 21 years of age and older, taxing them at a rate of 15 percent to fund enforcement and schools.

In Nevada, the ballot measure’s chances of success are strengthened by a number of strong union endorsements. These include the 57,000 member-strong Culinary Workers Union, the United Food & Commercial Workers International Union, local chapters of the International Brotherhood of Teamsters, and the International Alliance of Theatrical Stage Employees Local 720. These groups hope that legalization will further encourage Nevada tourism, leading to increased jobs.

When it comes to money, the donors opposing the measure are many of the same people who also opposed California’s proposal. Julie Schauer, a retired art professor, donated $1.4 million of the $2 million raised to oppose legalization in California. She also donated $30,000 in support of opposition efforts in Nevada.

Other groups opposing the measure are involved in the casino business. This includes billionaire casino owner Sheldon Adelson, whose $2 million donation provided the bulk of the opposition funds, as well as MGM Resorts International and the South Point Hotel & Casino.

The resort and gaming industries fear that legalization could put their gaming licenses in jeopardy.

“Marijuana use and possession is still illegal under federal law,” said the Nevada Resort Association, which opposes legalization. “Further, NRA members hold privileged, non-restricted gaming licenses and the Nevada Gaming Control Board (GCB) has expressed concerns about licensees participating in the marijuana industry. As gaming license is a privilege in Nevada and licensees are held to very strict standards, the NRA is opposed to passage of Question 2.”

The industry is joined by various public safety groups including the Nevada Sheriffs’ and Chiefs’ Association.

Across the border in Arizona, however, the business interests are more muddy. There, the legalization measure has the support of national groups such as the Marijuana Policy Project and the National Organization for the Reform of Marijuana Laws (NORML), as well as financial support from Arizona Grass Roots Dispensary, High Mountain Health, and YiLoLife, Inc., all medical marijuana companies.

But the opposition side has gained the support of one of the boogeymen of American politics–big pharma. Insys Therapeutics is the leading donor opposing Proposition 205, having contributed $500,000 out of the $1.8 million raised.

Insys is developing a product called the Dronabinol Oral Solution, which would administer a synthetic version of tetrahydrocannabinol (THC). The product could be used to treat nausea and vomiting associated with chemotherapy. Legalized marijuana would be a direct threat to the company, which touts its “capability to develop pharmaceutical cannabinoids” on its website.

The company has been struggling after accusations that it engaged in shady business practices to boost prescriptions of another of its products, the painkiller fentanyl. Their donation seems to have been too little, too late, as the most recent polling shows the legislation measure leading by 9 points in Arizona.

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