Expanding Medicaid under Proposition 3 would turn Utah’s budget on its head and put the state on a road to bankruptcy, a dozen Republican lawmakers warned Wednesday.

And Sen. Jacob Anderegg, R-Lehi, said he’s prepared to sponsor legislation repealing Proposition 3 if voters approve the initiative in November.

“With the public vote, I don’t think that that’s sacrosanct,” he said. “If we don’t [repeal Prop 3] and the numbers turn out where we think they are, I don’t know how we’re going to fund it.”

Utah’s Legislature has defeated past attempts at full expansion of Medicaid in the state. But while individual lawmakers have voiced opposition to Proposition 3, Wednesday’s statements — delivered in the state Capitol Rotunda — was the most visible and aggressive attack against the initiative in the current election cycle.

The gathering of legislative opponents — which included House Speaker Greg Hughes, R-Draper — was also held on the same day that the Prop 3-backing Utah Health Policy Project (UHPP) released a report estimating the creation of roughly 14,000 jobs in the first year after implementation of full Medicaid expansion.

“A healthier population helps all of us,” UHPP policy analyst Stacy Stanford said. “We see huge economic benefits that come from expansion."

Leah Hogsten | The Salt Lake Tribune l-r RyLee Curtis, with Utah Decides Healthcare and Rep. Ray Ward, R-Bountiful, listen as House Speaker Greg Hughes, R-Draper and fellow legislators against Proposition 3 talk against expanding Medicaid in Utah, Wednesday Oct. 17, 2018, in the rotunda of the Capitol. UtahÕs Legislature has defeated past attempts at full expansion of Medicaid in the state.

If approved by voters, Proposition 3 would combine roughly $90 million — through a state sales tax increase of 0.15 percent — with $800 million in new federal funding to provide health care coverage to 150,000 low-income Utahns.

The coverage level would exceed that of a partial expansion plan approved earlier this year by lawmakers, which has not yet received federal approval.

Hughes said he’s spoken with the leaders of other states where Medicaid has been expanded. The consistent message, he said, is that Medicaid costs have exceeded expectations and put a strain on government spending.

“That budget grows,” he said. “And they don’t have ways to slow that down and it comes at a price.”

It would be wrong to make promises to those in need that the state can’t deliver, Hughes said. And the way for lawmakers to help low-income Utahns, he said, is through the careful allocation of state resources.

“We can’t ignore the bottom line,” he said. “We can’t ignore the budget.”

Rep. Paul Ray, R-Clearfield, is the co-chairman of the Social Services Appropriations Committee. He said Medicaid costs will “skyrocket” under a full expansion plan, which will require him to pull funding from other programs.

“I’m going to cut [services for] children and I’m going to cut disabled people because I have no other option,” Ray said. “This is really a terrible idea. It’s not needed and it’s going to be very expensive to the taxpayers.”

But Rep. Ray Ward, R-Bountiful, disagreed with his colleagues in the Legislature. He said budget challenges related to health care are universal, in states that both have and have not expanded Medicaid.

And while full-expansion states have seen their costs rise, Ward said, none have attempted to pull back from expansion.

“Every one of them fully intends to continue the program and keep those people covered,” said Ward, a physician. “Other states have figured out a way to make this work — their people are benefitting. And we can figure out a way to make it work.”

Stanford said there’s a “ripple effect” to expanding Medicaid, as federal dollars are injected into the state’s health-care system and a healthier workforce contributes to the economy.

And Utah taxpayers are currently subsidizing Medicaid patients in other state, she said, instead of the individuals and families in their own communities.

“When we shift that money back to Utah, we see a really direct benefit in our economy," Stanford said, “including the creation of thousands of jobs every year.”

A new poll released Thursday by The Salt Lake Tribune and Hinckley Institute of Politics shows a 59 percent majority of registered voters in support of Proposition 3. And the opposition by lawmakers arrived late in the election cycle, with less than three weeks to go before balloting and by-mail voting underway.

Anderegg said he’s not worried about the political blowback of potentially repealing a voter-approved initiative.

“In my Senate district?” he said. “Not at all.”

He said he expects the partial expansion bill approved earlier this year to continue to have support among lawmakers. And he will work to persuade any of his colleagues who are reluctant to overturn a vote of the public.

“It may sway some,” he said. “I don’t know.”

Clarification: This story has been updated to reflect new polling by The Salt Lake Tribune and Hinckley Institute of Politics