AUGUSTA, Maine — Proponents of plans to build racetrack casinos in Biddeford and Calais have filed petitions seeking to change Maine law to allow for additional gambling facilities in the state.

If certified by the secretary of state, the petition would force a statewide referendum on whether to remove a long-expired deadline that prevents the operator of Scarborough Downs from reopening as a harness racing track and slots facility in Biddeford.

Additionally, the proposal would remove a requirement that racinos in Maine be located at least 100 miles apart and would authorize a racino in Washington County operated by the Passamaquoddy Tribe.

But first, lawmakers will have a chance to weigh in on the issue. If the Legislature approves the proposals — and Gov. Paul LePage agrees — the changes will take effect without a statewide vote.

The proposal seeks to correct what the petition’s authors claim is an inequity in the 2003 law that allowed Hollywood Slots to open Maine’s first racino on Main Street in Bangor.

When voters approved a ballot question authorizing the creation of two slots facilities near the harness racing tracks in Bangor and Scarborough, they required residents of the two cities to support the plans in subsequent votes.

But Scarborough voters balked at the plan and the project backers missed the Dec. 30, 2003, deadline. Scarborough Downs owners since have won approval from Biddeford residents to build a new facility in that town.

Supporters claim that having two slots facilities is critical to the survival of Maine’s harness racing industry, which now receives a portion of revenues from Hollywood Slots.

“We are optimistic legislators will correct an apparent inequity in the deadline for local approval of racinos at both of Maine’s commercial tracks and help make Biddeford Downs a reality for the good of all Mainers,” Tom Walsh, founder of Ocean Properties Ltd., one of the partners in the Biddeford Downs project, said in a statement.

The petition also calls for eliminating the exclusion zone that prohibits new gambling facilities from opening within 100 miles of another gambling establishment. Biddeford is within 100 miles of the four-season resort casino in Oxford County that voters approved in November.

If approved by lawmakers or voters, Passamaquoddy tribal members hope to build a racetrack and casino in Calais in a spot overlooking the St. Croix River and the International Bridge. The tribe has failed several times at the ballot box to win approval for a racino.

“The harness racing community has a rich history of preserving and protecting some of Maine’s most beautiful and productive open farmland, a history that makes the harness racing community a natural ally with Maine’s Native Americans,” Chief Clayton Cleaves of the Passamaquoddy Tribe at Pleasant Point said in a statement.