SACRAMENTO — Just weeks after it appeared headed for passage, California’s right-to-die bill ran headlong into some Democratic lawmakers’ fears that doctors might coerce the poor to end their lives when they become seriously ill — and was shelved for the year.

Sens. Lois Wolk, D-Davis, and Bill Monning, D-Monterey, conceded Tuesday that their legislation — dubbed a “death with dignity” bill by proponents and an “assisted suicide” measure by opponents — didn’t have enough support from members of the Assembly Health Committee to advance to the Assembly floor.

SB128 couldn’t overcome the concerns of lawmakers like Assemblywoman Lorena Gonzalez, D-San Diego, whose mother died in 2007 after a long battle with breast cancer. “I’m uncomfortable based on the experiences of my mom, who died of terminal illness,” she said Tuesday.

Gonzalez was one of several Southern California Democrats on the health committee who in recent weeks was lobbied heavily by the Catholic Archdiocese of Los Angeles to oppose the bill.

“I’m uncomfortable based on the impact this will have on poor people in a health care system that cuts corners in the name of costs, and I’m uncomfortable with the way suicide could be viewed across society, not just the terminally ill,” Gonzalez added.

Proponents, however, vowed not to give up. They noted that it was a two-year bill that could be resurrected next year. And they said they might seek to put the issue on the 2016 ballot since polls have shown wide support for it among Californians.

The bill would have allowed mentally competent, terminally ill patients to obtain a legal dose of medication from a physician to ease their suffering by ending their lives. It was inspired by Brittany Maynard, a UC Berkeley graduate and newlywed diagnosed with aggressive terminal brain cancer.

She could not receive physician-prescribed medication to end her life last year at her Alamo home, so she and her husband moved to Portland, Oregon, to take advantage of the state’s Death with Dignity law. Before her death, Maynard recorded a video, urging lawmakers to pass similar legislation in California.

“No one should have to leave their home and community for peace of mind, to escape suffering, and to plan for a gentle death,” Maynard said in the video.

“I am a little disappointed today in certain Assembly members, who aren’t representing their constituents, because we do have support in the Catholic and Latino communities,” Dan Diaz, Maynard’s widower, said Tuesday. “But I am in this for the long term. We will get there. I am not discouraged, just more determined to keep my promise to Brittany.”

Unlike another highly contentious bill debated by lawmakers this session that mandates vaccines for almost all schoolchildren and was signed into law by Gov. Jerry Brown, SB128 doesn’t have solid support from doctors, religious leaders or members of both major parties. That made it tough for proponents to build a coalition to back the measure.

Wolk and Monning both insisted Tuesday that the measure “isn’t dead” and that they remain committed to getting the bill passed and signed into law.

“This isn’t a theoretical debate,” Monning said. “This involves real people right now who are living with terminal illnesses, and we take that urgency to heart in exploring all options.”

George Eighmey of the Portland-based Death With Dignity National Center, who as a Oregon legislator had championed its law, said: “It is not a defeat, it is a regrouping, so we can respond to concerns expressed by several legislators who weren’t yet ready to commit one way or another — and who had heard a great deal from the hierarchy in the Catholic Church.”

But other observers see the stalled Assembly committee vote as a huge blow to the momentum Maynard’s story had breathed into the aid-in-dying movement in California and nationally.

Like California, at least 13 other states considered but did not pass aid-in-dying bills this session, according to the Death With Dignity National Center. About 11 states are still considering such legislation.

“It is a tremendous loss,” said Eli Stutsman, a Portland attorney who co-authored the Oregon Death With Dignity Act in 1993 and served as the lead political and legal strategist during the 1994 ballot measure campaign to pass the law. “What is a real shame is that the Senate did such hard and fabulous work, and voters overwhelmingly approve this type of policy.

“It would take several years of planning and budgeting and funding to wage a meaningful ballot campaign in California on this issue,” he added. “Opponents would spend millions of dollars. … The Catholic Church has the ability to raise the money and the willingness to spend it.”

The Senate last month passed the measure 23- 15 — with all but one of the Democrats present supporting it, and all Republicans opposed.

The first Assembly hearing in the 19-member health committee was delayed in late June until Tuesday. Ten votes are needed to move the bill forward — and only six or seven are guaranteed. The committee has 13 Democrats.

Assemblyman Miguel Santiago, D-Los Angeles, a member of the committee, said he’s had many conversations with supporters and opponents of the bill and that both sides have made compelling arguments. Ultimately, he said he struggled to find a reason to support it.

“My feelings regarding SB128 and the issue of aid in dying have been impacted by my life experiences and are personal to me,” he said.

Contact Jessica Calefati at 916-441-2101. Follow her at Twitter.com/Calefati.