AUGUSTA -- A Biddeford legislator is at work on a charter schools compromise as lawmakers prepare for debate on a bill that would allow the independently run schools in Maine.

Democratic Rep. Alan Casavant is proposing further limits on charter schools following a legislative panel's 8-5 vote in May against the charter schools bill, sponsored by Sen. Dennis Damon, D-Trenton.

Charter schools opponents -- including the state's largest teachers' union and a group representing Maine's school boards and superintendents -- have said introducing the new schools would divert too many students and resources away from locally funded public schools at a time when they're struggling to make ends meet.

While Casavant supported the bill in its initial form, he's proposing to limit the total number of charter schools in Maine to 20 during a 10-year pilot period for the independent schools in an effort to gain some votes.

That's down from the 40 schools that would have been allowed under the version of the bill rejected by members of the Legislature's Education Committee.

Casavant is also proposing that a charter school be allowed to enroll only 5 percent of a school district's students. The initial bill set that number at 10 percent.

Since charter schools would receive funds from students' home school districts on a per-student basis, limiting the number of students reduces the funds a district loses to a charter school.

"I thought that by talking to the proponents of the bill, and then tweaking it a bit, that a few more (opponents) would come over," Casavant wrote in an e-mail.

But it's unclear if Casavant's amendments -- which would go to legislators as part of the Education Committee's minority report -- would satisfy those lawmakers who would otherwise vote against the bill.

"They definitely address some of the bigger obstacles I had with the bill," said Sen. Justin Alfond, D-Portland, who co-sponsored but ultimately voted against the bill on the Education Committee. "That being said, I still am unconvinced that this is financially sustainable for Maine now and definitely in the future."

Casavant's amendments would also require that charter schools have 75 percent of their teachers certified, up from the 50 percent outlined in the legislation. And his proposals would deny charter school operators the ability to appeal the decision of their authorizer to end a charter.

But Rep. Edward Finch, D-Fairfield, said those amendments don't address all his concerns with allowing charter schools in Maine.

"You could have an outside entity basically take funding away from a local school without their authorization," he said. "If it's a local unit chartering within their own area, that's one thing. But the authorizer could be a college, which really, the local administrators would have no control over."

Damon, the bill's sponsor, said he "could go along with" Casavant's changes in order to "get Maine involved in the charter school program."

"It wouldn't be my first choice, but legislation is a series of compromises," Damon said. "But one would hope that the compromises don't dilute the reason for the bill."

While the fate of the charter schools bill in the Legislature is unclear, the state's electorate appears largely to be in support of allowing the independently run schools in the state, according to a recent poll.

A tracking survey by the Portland market research firm Critical Insights found that 70 percent of registered voters support allowing charter schools in Maine, one of 10 states that do not allow the schools.

The firm released the survey Friday after interviewing 601 residents by phone from May 14 to May 20.

The margin of error was plus or minus 4 percent, according to Critical Insights President MaryEllen FitzGerald.

Support for charter schools was highest in southern Maine, with 76 percent of those polled in that region backing the schools.

In central Maine, support was at 68 percent, with 65 percent of voters each in coastal and northern Maine backing charter schools.

Maine's charter school debate comes as President Barack Obama's administration is pushing states to do away with limits on the independent schools.

U.S. Education Secretary Arne Duncan hinted recently that the federal government might withhold money from a $4.35 billion discretionary fund meant for education reform from states that do not allow charter schools.

Matthew Stone -- 623-3811, ext. 435

mstone@centralmaine.com