Major League Baseball on Friday announced its support of an initiative that would authorize online sports betting in California, becoming the first major sports league to take sides in the high-stakes battle between bookmaking giants and the state’s powerful tribal gaming operators.

Two primary sports betting initiatives are on the November ballot. Proposition 26 would restrict betting to in-person only at tribal casinos and four horse racing tracks. Proposition 27 would allow online sports betting.

MLB is supporting Proposition 27, The California Solutions to Homeless and Mental Health Act. It is backed by a coalition of sportsbook operators, including DraftKings and FanDuel. A percentage of the revenue from Proposition 27 would be dedicated to fighting the homeless crisis in California.