A bill that would allow unenrolled voters to participate in primary elections won bipartisan support in the state Senate on Tuesday, suggesting potential momentum on an issue that has been debated in Maine for years.

Two years ago, a proposal to allow unenrolled or independent voters to cast ballots in party primaries failed in both the Maine House and the Senate. On Tuesday, however, the Senate voted 27-7 to give initial approval to a bill that would create “semi-open primaries” enabling independent voters to vote in a political party’s primary during each election cycle without having to enroll in that party.

Six Republican senators joined 21 Democrats in supporting the measure, L.D. 231, which now goes to the Democratic-controlled House for consideration. If enacted, the change would take effect for the 2024 elections, meaning it won’t be in effect for the congressional, gubernatorial and legislative elections in 2022.

Sen. Chloe Maxmin, D-Nobleboro, said the bill represented a step toward “a more inclusive process” given the proportion of Maine voters who are not members of any political party but who, as taxpayers, still help pay for state elections. According to data from the Maine Secretary of State’s office, 32 percent of voters were unenrolled in Maine on Election Day last year.

“The biggest thing that I heard from my constituents when I was campaigning is the need to feel heard and represented,” Maxmin told her Senate colleagues. “I think the fact that almost one-third of our population here in Maine cannot participate in our primary system is a good reason to not feel heard or  represented. And this bill is one step to creating a more inclusive, representative democracy.”

Sen. Matthew Pouliot, an Augusta Republican who serves as his party’s assistant minority leader, agreed that it is important to allow unenrolled voters to participate in elections they subsidize. But Pouliot also acknowledged that engaging unenrolled voters in primaries could be a base-building opportunity for Republicans and Democrats.

“I believe this legislation will give both parties opportunity to engage more voters who may or may not choose to eventually join a party,” Pouliot said during a Senate floor speech. “This is common-sense legislation that we should support.”

For years, unenrolled voters were the largest voting block in Maine. But Democrats have made considerable headway in recent years – particularly during the Trump era – and now account for 35 percent of the state’s 1.1 million active registered voters. Roughly 28 percent of registered voters were enrolled in the Republican party last November, while 4 percent were enrolled in the Green Independent Party.

Maxmin’s bill would create “semi-open primaries” in Maine because it would still prohibit individuals registered with one party from casting ballots in another party’s primary elections. Currently, people who want to change their party registration must do so at least 15 days prior to a primary election, caucus or convention in order to participate unless they are also changing their town of residence. That would not change under Maxmin’s bill.

A group called Open Primaries Maine has been advocating for the change this year and enlisting bipartisan support for the bill. Former Republican U.S. Sen. Olympia Snowe, for instance, recently announced her support for the measure.

“Power resides with the people through the ballot box,” Snowe said in a statement this month. “In order to help ensure that candidates better reflect the ideological pragmatism of most Americans, Maine should enact semi-open primaries.”

The House will likely take up the bill in the coming days.

In other election-related votes, Senate Democrats defeated several bills that would have required voters to show a photo ID in order to cast a ballot. Democrats already had voted overwhelmingly in the House to defeat photo ID voting measures.

In other news, the Maine House narrowly rejected a measure that would have allowed towns and cities to impose an additional 1 percent local tax on lodging and prepared foods. The bill failed on a 69-74 vote.

Leaders in several of Maine’s larger towns and cities as well as tourism hotspots have been advocating for a so-called “local option sales tax” for years. Supporters argue that the revenue would help reduce the burden shouldered by local property taxpayers for the upkeep of roads and other infrastructure as well as for providing police, fire and social services.

The bill sponsored by Rep. Mike Sylvester, D-Portland, would require 60 percent of voters to support a local option sales tax during a referendum before city or municipal officials could impose it. The measure would have allowed municipalities to keep 90 percent of the resulting revenues but would direct 10 percent to the Maine State Housing Authority for rental assistance and property tax abatement.

“If you are a town that doesn’t want it, you don’t have to do it,” said Rep. Benjamin Collings, D-Portland. “It’s not going to cost you a penny and it’s not going to hurt you.”

But opponents called the tax “regressive” because it also would have to be paid by lower-income individuals who buy prepared food. They also warned that it could crack open the gate to future tax increases and could impact decisions tourists make about where to stay or dine.

In other State House action Tuesday:

• The House passed a measure that would require the state to meet a voter-approved law that state government fund public education in Maine at 55 percent. The 133-9 House vote for the bill follows a 33-0 vote for the bill in the Senate on Monday. The bill will face additional votes but essentially affirms the position of Democratic Gov. Janet Mills, who has included the funding in a proposed budget change package that is currently before the Legislature. The proposal would cost state government an additional $107 million a year starting in 2022.

• The Senate passed a bill that would allow the Secretary of State to reject vulgar and profane vanity license plates. The bill passed the Senate on a unanimous voice vote and now will move to the House for consideration.

• Several gun control measures were voted down in the House on Tuesday, including a measure that would require federal background checks for private gun sales that are advertised or for guns sold in private sales at gun shows. Another bill that would ban bump stocks in Maine also was voted down in the House with opponents of the measure arguing the devices already are banned under federal law.

•  The Senate voted 19-13 to give preliminary approval to a bill that would require the state to divest from all investment in fossil fuel companies. The House had approved the bill, L.D. 99, on a 80-57 vote last week. Additional votes are expected.

• The House also overwhelmingly approved a bill sponsored by Rep. Rachel Talbot Ross, D-Portland, that would incorporate African American studies into Maine’s statewide learning standards, know as the Maine Learning Results. The bill also requires Holocaust and genocide education be added to the learning standards for Maine’s public school students in grades K-12.

“Maine children can go through their entire educational experience – kindergarten through college – in our public schools today with little exposure to this history,” Talbot Ross said in prepared statement following the vote. “Its absence is not only detrimental to African American students, but to all of us. This measure brings forth efforts made by generations of Maine’s African American community to have their experiences taught as part of our state’s history.”

Correction: This story was updated at 8:19 a.m. on June 9, 2021 to correct that a semi-open primaries bill failed to pass the Maine House in 2019.