LAS VEGAS -- Rank-and-file Democrats appear to be shifting to the middle on health care, worried about what's politically achievable on their party's top 2020 issue.
While "Medicare for All" remains hugely popular, the majority say they'd prefer building on "Obamacare" to expand coverage instead of a new government program that replaces America's mix of private and public insurance.
Highlighted by a recent national poll, the shifting views are echoed in interviews with voters and the evolving positions of Democratic presidential candidates . Some have backed away from the government-run plan championed by Sens. Bernie Sanders of Vermont and Elizabeth Warren of Massachusetts that for months had seemed to be gaining momentum.
It could mean trouble for Sanders and his supporters, signaling a limit to how far Democratic voters are willing to move to the left amid doubts that Americans would back such dramatic changes to their health care.
"We hear Medicare for All, but I'm not absolutely certain what that means and what that would then mean for me," said Democrat Terrie Dietrich, who lives near Las Vegas. "Does it mean that private insurance is gone forever?"
Dietrich, 74, has Medicare and supplements that with private insurance, an arrangement she said she's pretty comfortable with.
She thinks it's important that everyone has health care, not just those who can afford it. She said she would support Medicare for All if it was the only way to achieve that.
But "I don't think we can ever get it passed," Dietrich added.
Erin Cross, her 54-year-old daughter and also a Democrat, said she's uncomfortable with switching to a system in which a government plan is the only choice. She said Democrats won't be able to appeal to Republicans unless they strike a middle ground and allow people to keep their private insurance.
"We've got to get some of these other people, these Republican voters, to come on over just to get rid of Trump," she said.
Democratic presidential candidates also have expressed skepticism.
California Sen. Kamala Harris' new plan would preserve a role for private insurance. New Jersey Sen. Cory Booker is open to step-by-step approaches. Meanwhile, health care moderates including former Vice President Joe Biden have been blunt in criticizing the government-run system envisioned by Sanders.
In Nevada, the early voting swing state that tests presidential candidates' appeal to labor and a diverse population, moderate Democrats have won statewide by focusing on health care affordability and preserving protections from President Barack Obama's law.
Nationwide, 55% of Democrats and independents who lean Democratic said in a poll last month they'd prefer building on Obama's Affordable Care Act instead of replacing it with Medicare for All. The survey by the nonpartisan Kaiser Family Foundation found 39% would prefer Medicare for All. Majorities of liberals and moderates concurred.
On a separate question, Democratic support for Medicare for All was a robust 72% in July, but that was down from 80% in April, a drop Kaiser says is statistically significant but not necessarily a definitive downward trend.
That said, Kaiser pollster Liz Hamel said it wouldn't be surprising if it turned into one. On big health care ideas, she said, "as the public starts seeing arguments for and against, we often see movement."
The Kaiser survey also found broad backing for the public-option alternative that moderates are touting, a government plan that would compete with but not replace private insurance. Eighty-five percent of Democrats supported that idea, along with 68% of independents. Republicans were opposed, 62% to 36%.
Large increases in federal spending and a significant expansion of government power are often cited as arguments against Medicare for All. However, the main criticism Democrats are hearing from some of their own candidates is that the Sanders plan would force people to give up their private health insurance. Under the Vermont senator's legislation, it would be unlawful for insurers or employers to offer coverage for benefits provided by the new government plan.
Ohio Rep. Tim Ryan argued during the last round of Democratic debates that that's problematic for union members with hard-fought health care plans secured by sacrificing wage increases. However, Sanders has long asserted his plan will allow unions to obtain bigger wage increases by taking health care out of the equation.
In interviews with The Associated Press, union workers in Nevada said they worried about how Medicare for All would affect their coverage.
Chad Neanover, prep cook at the Margaritaville casino-restaurant on the Las Vegas Strip, said he would be reluctant to give up the comprehensive insurance that his union has fought to keep. He has asthma, and his wife is dealing with diabetes. The union's plan has no monthly premium cost and no deductible.
"I don't want to give up my health insurance. I've personally been involved in the fight to keep it," said Neanover, 44. "A lot of people have fought to have what we have today."
Savannah Palmira, a 34-year-old union construction worker in Las Vegas, said she's open to supporting Medicare for All, but wants to know specifically what it would look like, how the country would transition and how it would affect her plan.
"That's one of the biggest things that I love about being in the union, is our quality health care," Palmira said.
Medicare for All backers say their plan has been unfairly portrayed.
"The shift in polling on Medicare for All is a direct result of mischaracterizations by opponents," said Rep. Ro Khanna, D-Calif., a Sanders campaign co-chair.
People are most interested in keeping their own doctors, Khanna added, and Medicare for All would not interfere with that.
Longtime watchers of America's health care debate see new energy among Democrats, along with a familiar pattern.
"The long-standing history of health reform is that people want to hang on to what they have," said Georgetown University public policy professor Judith Feder, who was a health policy adviser in the Clinton administration.
Nonetheless, she noted a common interest among Democrats: "People want affordable, reliable, stable coverage."
Alonso-Zaldivar reported from Washington.