AUGUSTA – Supporters of a referendum proposal to allow tax credits for Maine college graduates who stay in the state to work collected more than enough voters’ signatures to put the question on next November’s ballot, state election officials said Monday.

A referendum will go forward unless the Legislature enacts the proposal first, an option that would delight initiative organizers from Opportunity Maine. The political action committee said its proposal has the support of labor and business groups as well as students.

The ballot question asks, “Do you want to allow a tax credit for college loan repayments to any taxpayer who earns a future college degree in Maine and continues to live and work in Maine?”

Besides helping to plug a “brain drain” of Maine graduates who go out of state to work, the proposal would help new degree-holders entering the work force to meet their school debts in addition to other living expenses.

“Should we really have to mortgage our futures in order to obtain a degree?” said Nicole Brown, chair of the University of Maine System student government.

The proposal would also give businesses an option of making the student loan payments for eligible employees and taking the tax credits for themselves, said Opportunity Maine President Andrew Bossie.

Supporters said the proposed tax credits would help Maine businesses by providing a better-educated work force, and attract companies that see a more skilled work force as a result of the tax breaks.

Maine now has 30 percent fewer degree holders than the rest of New England, and its average incomes are 30 percent lower than the rest of New England, according to initiative organizers. But at the same time, the burden of student debt is rising, it says.

The new state cost of the tax breaks would be absorbed at least in part by higher pay scales resulting from having more college-educated workers in the state, said Bossie.

“We know that a lot of people need to leave Maine after they graduate because they can’t afford to pay their student loans,” said Bossie, who expects to graduate this spring from the University of Southern Maine with $27,000 in loans outstanding. The tax credits would not apply retroactively to students who graduated before the measure’s enactment.

Opportunity Maine estimates that a worker in 2008 will earn more than $16,000 per year more with a bachelor’s degree than with a high school diploma, and $10,000 more with an associate’s degree.

It also says 61 percent of Maine students pursuing associate’s and bachelor’s degrees have student loans, and for this year’s graduates, the average debts will be more than $10,000 for associate’s degrees and nearly $22,000 for bachelor’s degrees.

Organizers said they started gathering signatures in September in hopes of exceeding the 55,087 minimum needed. They ended up submitting more than 73,000 to the Secretary of State’s office, which accepted 63,285 signatures and rejected 10,106.