The Seminole Tribe of Florida is getting behind a push to put an anti-gambling amendment on next year's ballot.

Newly filed campaign finance records show the tribe gave $1 million in October to the group Voters in Charge, which wants Floridians to pass a constitutional amendment in 2018 that would require voter approval for new casinos.

The Seminoles already operate several casinos in the state and have an agreement that allows them to offer specific types of gambling, including blackjack. But legislators in recent years have considered allowing additional casinos in the state.

Disney is also backing the anti-gambling amendment and has donated nearly $3 million.

Voters in Charge needs 800,000 valid signatures to make the ballot. So far, officials have verified nearly 400,000 signatures.