The House Republicans’ victory on Thursday in passing a bill to repeal and replace “Obamacare” couldn’t have happened without the unanimous support from the 14 members of California’s GOP congressional delegation.

Those votes drew praise from some Californians convinced Obamacare has been a burden and must go. But healthcare advocates around the state called the votes a stunning reversal — some said “betrayal” — by several representatives who previously had cited serious concerns about the GOP legislation, which was opposed by all 39 House Democrats.

Most egregious, the advocates say, were the votes by U.S. Reps. Jeff Denham, R-Turlock; David Valadao, R-Hanford; and Steve Knight, R-Lancaster, who just the day before had either told the public — or whose staffs had told reporters — that they were “undecided.”

Unknown to most Californians, however, all three had quietly signed on earlier in the day as co-sponsors to an amendment designed to ease the bill’s passage.

“California Congress members who voted for this monstrosity betrayed their constituents given the disproportionate impact in our state,” said Anthony Wright, executive director of Health Access California. “They voted to leave 4 to 5 million Californians uninsured, to spike premiums and deductibles for millions, (and) take away patient protections from people with pre-existing conditions. Voters will surely remember and not take kindly to this vote.”

Denham, for one, already is facing a new challenger for his seat by a well-funded Bay Area Democrat, 30-year-old venture capitalist Josh Harder.

Knight was unapologetic Thursday.

“As a husband to a nurse, I’ve seen firsthand the challenges families and patients face under our current health law, which is why today I voted in support of the American Health Care Act,” Knight said in a statement released after the vote. “I believe that our nation’s families deserve a health care system that is affordable and sustainable, not just for the next five years, but for generations to come.”

Should the GOP bill become law, nonpartisan congressional analysts estimate 24 million more Americans would be uninsured by 2026, including 14 million by next year.

“This bill would cut about 1 trillion dollars nationally in federal support for health care, scaling back Medicaid and tax credits that help people pay their insurance premiums,” said Larry Levitt, a senior vice president at the Menlo Park-based Kaiser Family Foundation.

“A whole lot of those cuts would come from California, which would see a setback in the progress made to reduce the ranks of the uninsured,” Levitt said. “This would be the biggest reversal of a government program ever.”

The reverberations are pronounced in California because it was one of the earliest states to embrace Obamacare, expand Medicaid to adults without children and establish a robust state health care exchange.

The law has resulted in the Golden State reducing its uninsured rate to a record low of 7.1 percent since 2013, just before the Affordable Care Act took full effect.

“California, having made the most progress under Obamacare, has the most to lose,’’ said Daniel Zingale, a senior vice president at the California Endowment, a private health foundation in Los Angeles that was among the state’s biggest backers of Obamacare. “I think a lot of people are wondering: Am I in that 24 million who are going to lose coverage?’’

The House bill radically restructures Medicaid financing and effectively rolls back the Affordable Care Act’s Medicaid expansion, cutting $880 billion over the next 10 years. It also eliminates the Medicaid expansion after 2020.

As a result, the number of Medicaid beneficiaries would fall by 14 million in 2026, according to the nonpartisan Congressional Budget Office. Most of those losing Medicaid would likely end up uninsured because they would not have access to affordable coverage, the CBO says.

Medi-Cal now covers 14.1 million Californians, more than a third of the state’s residents. Four million of those adults are enrolled through the Medicaid expansion.

The House Republican proposal also imposes draconian requirements for Medicaid eligibility and permits severe cuts in benefits.

Dr. Michelle Quiogue, president of the 9,700-member California Academy of Family Physicians, was among those who condemned Thursday’s vote.

“We are deeply discouraged,” she said. “We call on the Senate to refuse passage of the American Health Care Act.”

California Assembly Speaker Anthony Rendon, D-Paramount, was more blunt.

“Today’s vote on Trumpcare proves that cowardice must be a pre-existing condition,” he said in a statement on Thursday.

House Majority Leader Kevin McCarthy, R-Bakersfield, and California Republicans in Congress “chose Donald Trump and Paul Ryan over the needs of their own constituents,” Rendon said. “They should be ashamed and they must be held accountable.”

Gov. Jerry Brown called the bill “cruel and ill-conceived…. rushed to a vote with no fiscal analysis.’’ He said it “will hurt American families and it’s bad for California. Millions will lose coverage, those with pre-existing conditions will be abandoned and costs will skyrocket. … The fig leaf amendments tacked on in the 11th hour don’t change this massive assault on so many decent and hard-working people.”

But in a joint statement, Valadao and Denham disputed Brown’s comments.

“At the cost of families in rural California, Gov. Brown has prioritized access to health care for those living in urban areas and along the coast over those most in need in the Central Valley,” they wrote. “If he truly cared about ensuring all Californians had access to health care, he would work to improve Medicaid reimbursement rates for the most prosperous state in the nation.”

Despite the staggering losses that loom for many Californians, others who have watched their health insurance premiums soar under a law they say is unfair welcomed the House passage of the Republican bill.

“The GOP needs to get this done. The 2018 elections are rapidly approaching,’’ said Sally Pipes, president and CEO of the San Francisco-based Pacific Research Institute, a nonprofit that promotes limited government.

She said GOP moderates were brought on board because the amended bill provides $8 billion more over five years to help states finance their high-risk pools. This late addition, aimed at winning over votes, is on top of $130 billion over a decade previously in the bill for states to help people afford coverage through high-risk pools.

But in California, where a high-risk pool was established in 1991, critics said it was plagued by long waiting lists, exorbitant premiums, low annual and lifetime benefit caps, coverage exclusions for pre-existing conditions and limited participation of health insurance carriers.