The union representing 4,000 registered nurses in Maine announced Wednesday that it supports a ballot effort to establish a publicly owned utility.

At a news conference in Portland, the Maine State Nurses Association said it supports Question 3 because it sees the reliable delivery of electricity as a matter of public health.

“It’s been proven that unreliable power truly hurts communities,” the union said in a statement. “Power loss has been linked to higher mortality rates, especially for our elders, due to a myriad of reasons. And Maine currently leads the nation in power outages.”

Backers of the referendum have promised better reliability and lower rates if the state takes over investor-owned utilities Central Maine Power and Versant and creates a public utility called Pine Tree Power. Those claims have not been verified by an analysis of the Maine Public Advocate.

Unions are split on the Nov. 7 ballot measure. Jason Shedlock, regional organizer at the Laborers’ International Union of North America, which opposes the Pine Tree Power proposal, said Wednesday that he disagrees with the nurses union.

“I credit them 100% for independent thinking or whatever,” he said at an editorial board meeting of the Press Herald. “I think that their data is not one that I would rely on.”

The International Brotherhood of Electrical Workers and Maine AFL-CIO oppose the ballot measure. The union says utility workers would become public employees of a publicly owned utility and would be denied the right to strike. It also said utility workers could face less “fair and equitable” treatment, similar to what the union says Maine state employees experience.

The IBEW said Maine state troopers have had to “endure furloughs, skipping pay periods and partial funding for retirement.”

Backers of Pine Tree Power say the new utility, if approved by voters, will contract with a private company to operate the grid and the utility workers will remain private sector employees.