Dreams of adding three more casinos to the state of Connecticut moved one step closer to reality on Monday, when a proposed bill passed through its second legislative committee.

Over the last month, the Mohegan and Mashantucket Pequot tribes in Connecticut have been fighting for a state bill that would allow them to operate slot machines together outside of their respective tribal reservations. The two tribes proposed the bill because revenues from their two operating casinos — Mohegan Sun and Foxwoods Resort Casino — are expected to take a plunge when two new large casinos open in Boston and Springfield, Massachusetts, said former Republican state Sen. Kevin Rennie. The bill passed through the Committee on Public Safety and Security in March and through the Committee on Planning and Development on Monday; it will be voted on by the Senate during the next session.

In the early 1990s, the tribes signed agreements with the state government allowing them to operate taxable slot machines on their reservations, even though those machines are illegal in the rest of Connecticut. If the current proposal were to pass, the tribes would have to reach a new agreement with the government about the terms and conditions of their exception, Rennie said.

“What happens in Connecticut is that, because they’re on Indian reservations, the political process is very limited,” Rennie said. “When you start licensing casinos outside of a licensed Indian tribe you get a lot of politics involved.”

Considering the past agreements with the tribes, State Attorney George Jepsen filed a letter to members of the state House of Representatives and Senate last week that raised legal concerns for the proposed legislation. Jepsen pointed out in his letter that allowing the tribes to expand their casino enterprises would give potential third parties legal basis to make a case for creating their own gambling businesses in Connecticut.

Jepsen also wrote that if the three Native American tribes in Connecticut that are currently seeking recognition from the Bureau of Indian Affairs succeed, those tribes would potentially seek to open casinos as well.

“The enactment of the proposed legislation, authorizing the tribes to conduct casino gambling under state law, could serve as a new trigger that would significantly increase the likelihood that newly acknowledged tribes would succeed in asserting their rights to casino gambling under the [Indian Gaming Regulatory Act],” Jepsen wrote.

Supporters of the bill argue that the new casinos would create thousands of jobs for Connecticut residents.

Jobs at the two casinos in Connecticut have been in jeopardy as the facilities face increasing competition from other states. Revenue from the two tribes’ gambling facilities has decreased over the last decade as new casinos have opened in New York and Massachusetts, Rennie said.

Although the specific locations for the three proposed casinos have not yet been determined, at least one will likely be located off of I-91 on the route from Hartford to Springfield, Massachusetts, said Adam Joseph, communications director for the Senate Democratic Caucus. Joseph, who supports the bill, added that because the new casinos will create new jobs, the bill will likely gain support from both sides of the aisle.

Still, the bill does not currently have widespread public support: A recent poll conducted by Quinnipiac University showed that only 36 percent of voters support the bill for three new casinos, which would all be relatively small casinos located on roads leading from Connecticut into Massachusetts and New York.

Doug Schwartz, director of the Quinnipiac University poll, said most respondents against the bill cited a concern about gambling addiction.

Nevada and Louisiana are the only two states where casino-style gambling is legal statewide.