Opponents of Oklahoma’s medical marijuana ballot measure raised and spent more than a million dollars in a little more than a month in an effort to defeat State Question 788, with oil and gas interests pouring more than half a million dollars to the effort, newly released campaign finance reports show.

The political action committee “SQ 788 is Not Medical,” which opposed the ballot measure, received nearly $1.3 million in donations between May 15 and June 30, according to the group’s filing with the Oklahoma Ethics Commission.

The political action committee, which is allowed to accept and spend unlimited amounts of money, was established after the ethics commission’s first quarter PAC filing deadline, meaning that its donors and much of its spending remained secret during the State Question 788 campaign, until Tuesday night’s filing.

In total, the group spent more than $1.1 million on television, radio and newspaper advertisements, as well as direct mail and other efforts to defeat State Question 788, leaving it with about $121,000 in the bank.

According to the group’s filing, Devon Energy, Newfield Exploration Company, and Continental Resources all donated $100,000 to the PAC, while other energy companies — Chesapeake Energy, Cimarex Energy Company, Enable Midstream Partners, Conoco Phillips and Gulfport Energy — all contributed between $25,000 and $75,000 each to the effort.

The effort by oil and gas interests to defeat the ballot initiative also extended beyond contributing money. The day of the election, Continental Resources CEO Harold Hamm sent a company-wide email urging employees to vote against the measure.

Several banks also donated funds to the group: Arvest Bank donated $25,000, Bancfirst donated $10,000 and IBC Bank donated $20,000. Meanwhile, the Chickasaw Nation donated $100,000 to SQ 788 is Not Medical.

The biggest single donor, however, was Forward Oklahoma City, a political arm of the Greater Oklahoma City Chamber of Commerce, which donated a total of $190,000 to SQ 788 is Not Medical. It was also the group’s first donor, records show, making a single $25,000 donation on May 15.

Tulsa’s Future Inc., an arm of the Tulsa Regional Chamber of Commerce, also donated $25,000 to the group, campaign filings show.

Meanwhile, the group that advocated for passage of the medical marijuana measure — Vote Yes on 788 — received around $176,000 in monetary donations and spent $172,000 during the campaign, Ethics Commission filings show.

Though most of the donations the group received were from individuals and under $1,000, the bulk of funding came from the medical marijuana trade group New Health Solutions Oklahoma, a nonprofit organization founded in January this year by Oklahoma City attorney and lobbyist Robert “Bud” Scott.

New Health Solutions Oklahoma gave $130,000 in monetary donations to the Yes on 788 group and about $91,000 in “in kind” donations, which consists of work done or expenses covered by the organization on behalf of the PAC.

In the days since State Question 788’s passage, Scott has been one of the loudest voices calling for Gov. Mary Fallin to call a special legislative session to allow legislators to draft laws concerning medical marijuana. Ethics records show New Health Solutions has hired at least nine lobbyists, including Scott himself, since this past spring.