AUGUSTA — The Maine House and Senate split Monday on a “right-to-die” bill that would allow terminally ill patients to end their own lives with drugs legally prescribed by their doctors.

The Senate narrowly rejected the bill on an 18-17 vote, only to see the House pass the measure on a 76-70 vote several hours later. The bill now heads back to the Senate, setting the stage for advocates to try to flip at least one vote on a bill that divided individuals and groups that work with the terminally ill.

The two close votes followed more than two hours of emotional debate among lawmakers who often recounted their own experiences of watching parents, spouses and close friends die, sometimes slowly and painfully. Those experiences influenced votes on both sides of the issue, and the bill’s fate remained unclear Monday evening.

“It is about dignity, it is about self-determination and it’s about the ability to choose one’s own path,” said Sen. Roger Katz, R-Augusta, the bill’s lead sponsor.

“I think we need to be thoughtful and careful because we are talking about the end of a human life,” an opponent of the bill, Sen. Andre Cushing, R-Hampden, said after sharing the story of his family’s difficult decisions after his father suffered an aneurysm. “I would hate to reach a point here in Maine where we have created an environment where we accept that the ending of a life has no value.”

Katz’s bill would make Maine the sixth state where terminally ill patients can request a lethal dose of prescription drugs from a willing physician. Although often described as physician-assisted suicide, the bill specifies that the patients – not the physicians – must self-administer the drugs at a time of their choosing.

The legislation is modeled after a law on the books in Vermont that supporters claim offers safeguards to prevent abuse. Oregon, Washington, New Mexico and Montana also have assisted-suicide laws.

Katz’s bill, L.D. 1270, specifies that patients would have to request the fatal drugs twice from the doctor during face-to-face interactions, with the second request coming no earlier than 15 days after the initial request. Patients must also put their wishes in writing and sign the document in front of two disinterested witnesses. Also, the patients would have to be judged mentally competent, and a second doctor would have to affirm that they are suffering from a terminal illness.

But bill opponents remained concerned about the potential for abuse. Several critics warned that the bill could create a slippery slope that leads to the type of “death clinics” seen in some European countries with legalized physician-assisted suicide or euthanasia of patients with mental illness, dementia or chronic depression. They also cautioned that the bill could lead to end-of-life decisions being based on financial considerations.

“These things happen when death becomes an acceptable solution to the suffering,” said Rep. Deb Sanderson, R-Chelsea. “Is this a door we are just starting to open? Where do we go from here? How much further will we take this? I think it’s rather frightening to think about.”

Numerous health and religious organizations testified against the bill during the public hearing process, including Disability Rights Maine, Maine Hospice Council, the Maine Medical Association and the Roman Catholic Diocese of Portland.

But several lawmakers with experience in the medical and hospice fields supported the measure.

Sen. Geoffrey Gratwick, D-Bangor, who is a physician, called the bill the most difficult issue he has had to deal with on a personal and professional level, but that he supported it.

Sen. David Dutremble, a Biddeford Democrat who is a firefighter and an EMT, said there have been numerous instances where patients with terminal illnesses opened up about their desire to end their own suffering.

“They can’t have those conversations in front of their families because family members get very upset,” Dutremble said. “But when they are alone in the back of the rescue (vehicle), they express themselves to us and many times we have had patients say, ‘I wish I had this option, but it does not exist.'”

The House and Senate votes fell largely but not exclusively along party lines, with Democrats supporting the measure and Republicans in opposition. Supporters will now have to work to change at least one vote in the Senate in the closing days of a legislative session in which numerous issues – including the contentious state budget – remain unresolved.