PORTLAND (AP) — Maine voters are getting ready to decide proposed changes to their state’s public campaign finance law as business interests disagree over the measure, the governor calls it “a scam” and a U.S. senator praises the effort to “pull back the curtain on secret money.”

The Mainers for Accountable Elections championed the proposal on Tuesday’s ballot, and said it will strengthen the law that gives public money to candidates running for governor and the Legislature. The group says the proposal would make more money available to qualifying candidates, increase fines for violators of the campaign finance laws and require groups to disclose some donors on political ads.

Passage would increase the money available to gubernatorial candidates to $3 million, group president Andrew Bossie said, adding that the amount was less than $2 million before the Legislature suspended it. It would also bolster the state’s allocation to its Maine Clean Election Fund from $2 million to $3 million per year.

Bossie said the measure rebuilds the 1996 law that was weakened by a 2011 U.S. Supreme Court ruling that allowed candidates to increase campaign coffers when they are being outspent. Participation in the program has fallen from 85 percent of sitting legislators in 2008 to about half, he said.

“This would restore clean elections to the strong law that people voted for,” Bossie said.

But the Maine State Chamber of Commerce points to a provision in the proposal that would eliminate $6 million in business tax incentives, which it said effectively takes money away from businesses and gives it to candidates. Chamber President Dana Connors said eliminating incentives would put Maine at a competitive disadvantage.

“It’s hard to compete with other states for business without incentive programs,” he said.

The Maine Small Business Coalition disagrees, and has issued a statement of support saying the changes “elevate the voice of small businesses.” The coalition says improved public campaign financing would keep big businesses from buying elections.

The squabble over the referendum has spilled over to politicians, including Republican Gov. Paul LePage. He denounces the proposal, saying that it will cost taxpayers and won’t get the influence of money out of politics. He says voters who approve of it are “gullible.”

Meanwhile, U.S. Sen. Angus King is among a group of politicians who have come out in favor of approving the referendum. The Maine independent and former governor says the changes “will pull back the curtain on secret money in elections by strengthening disclosure rules so that Mainers know who is truly trying to influence their vote.”

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