AUGUSTA — A bill that could make it more difficult to get a referendum question on the Maine ballot is on the verge of being passed by the Legislature.

The proposal would amend the Maine Constitution to require sponsors of ballot campaigns to obtain a percentage of voter signatures from each of Maine’s two congressional districts to qualify for the ballot. The House gave initial approval to the bill Tuesday, 99-47, and the Senate voted 32-3 on Monday. Additional votes are required before the proposal is sent to Gov. Paul LePage.

Supporters of the bill say the geographical requirement is designed to ensure that proponents of a ballot question show that their proposal has support statewide, not just among the citizens of the state’s more-populated southern areas.

Several supporters cited the 2014 bear-baiting ban referendum as an example of a ballot question advanced by out-of-state interests who targeted more liberal communities such as Portland to obtain signatures and get an issue on the ballot.

The bear-baiting measure was defeated by voters, 53 percent to 46 percent. Voters in rural districts strongly opposed the referendum, often by lopsided margins. However, southern Maine voters were more supportive of the bear hunting restrictions. In Portland, for example, voters favored the ban by 68 percent to 32 percent.

The Secretary of State’s Office could not immediately provide data showing the geographical breakdown of signatures gathered for the 2014 referendum. However, Secretary of State Matt Dunlap said between 70 percent and 80 percent of the signatures were from Cumberland County.

The proposal is one of several introduced this session that have used the bear-baiting referendum as an impetus to change the state’s election laws. In May, the Legislature approved a bill that will make it harder for out-of-staters to participate in the signature-gathering process to put a question the ballot. LePage signed the bill into law on May 24. It could affect future referendums, including another anticipated bear-baiting referendum question, because some campaigns depend on out-of-state organizations that specialize in collecting signatures.

The Sportsman’s Alliance of Maine, a pro-hunting group that played a lead role in opposing the bear-baiting referendum, drafted the signature-gathering bill. The Humane Society of the United States, a national group that bankrolled the bear-baiting campaign, opposed the bill. So did the American Civil Liberties Union of Maine, which argued that the bill restricts the constitutional right to political speech.

Now a proposal that will add a geographical requirement to the signature-gathering process is moving toward enactment. The bill, L.D. 742, is sponsored by Sen. Tom Saviello, R-Wilton. The initial votes taken Monday and Tuesday suggest that the two-thirds margin needed for enactment is attainable in the House and the Senate.

The bill would then require approval by a simple majority of voters, who have the final say in amending the Maine Constitution.

Currently there are no requirements that signatures be obtained from specific geographic areas, and campaigns need only obtain a number of signatures that equals at least 10 percent of the total votes cast in the previous gubernatorial election. Based on the election in November, referendum campaigns would need 61,123 signatures to get on the ballot.

The proposal advanced Tuesday by the House would require the number of signatures obtained by campaigns to be at least 10 percent of the total gubernatorial votes in the 1st Congressional District – southern and coastal Maine – and 10 percent of the total gubernatorial votes in the 2nd Congressional District – western, northern and Downeast Maine.

Maine is among the 24 states that allow citizens to petition the government to enact new laws, according to the National Conference of State Legislatures. Some states have tried to enact a geographical requirement to the signature-gathering process. In 2007, the Nevada Legislature passed such a requirement. The law was challenged in court by opponents who argued that it gave more influence to the voters in a congressional district where petitioners can’t obtain the 10 percent signature threshold.

However, the 9th U.S. Circuit Court of Appeals ruled in 2012 that the law was legal.

Rep. Louis Luchini, D-Ellsworth, said the Maine proposal was modeled after the Nevada law. He said it was designed to make sure ballot campaigns had support statewide, and not just in more populous regions.

Rep. Diane Russell, D-Portland, argued that the proposal will make it more difficult for Mainers to petition for new laws. Russell, who is involved in a campaign for a ballot question to legalize marijuana, said the signature validation process usually occurs late, and that campaigns may not find out until it’s too late that they haven’t met the geographical threshold.