Gov. Gary Herbert signed a measure Tuesday to give more than 70,000 needy Utahns access to government health coverage, ending years of failed attempts on Capitol Hill to expand Medicaid in the state.

But whether House Bill 472 ever takes effect still remains uncertain. Under President Obama’s signature Affordable Care Act (ACA), the Utah law needs approval by the federal Centers for Medicare and Medicaid Services (CMS), which has sent mixed signals on whether it will fully sign off.

Even if CMS does approve HB472, it will likely be about a year — even on an aggressive schedule — before the state can begin enrolling people for coverage. Meanwhile, a competing Utah citizens initiative that would expand Medicaid coverage more widely than HB472 also continues to gather signatures for a spot on November’s ballot.

At a signing ceremony Tuesday at the Utah Capitol, Herbert, lawmakers and other officials were nonetheless thrilled to make it this far. Past efforts to expand Medicaid under the ACA failed repeatedly as conservative lawmakers expressed concern over potentially ballooning costs.

“It’s had its twists and turns, its bumps and bruises, to get us to this point here today,” said Herbert, referring to five years of failed attempts at large Medicaid expansions in Utah. (A small-scale expansion covering a few thousand homeless people and low-income parents took effect last year.)

“This allows us to buy something today, that we can afford tomorrow,” Herbert added of HB472, which includes a spending cap and repurposes money from other Medicaid programs to cover the state’s share of costs.

Under the new law, the feds would pay 90 percent, and the program would automatically end if federal officials were to lower that commitment. Total state and federal costs for the expansion would rise over the next few years, reaching about $500 million by 2024.

HB472 also requires enrollees to prove they are working or participating in volunteering, vocational training or similar activities. The Trump administration has told state officials it is receptive to such tweaks requested by individual states, which were nonstarters under the Obama administration.

“Medicaid should be a partnership between the federal government and the states, not just a top-down program,” said Senate President Wayne Niederhauser, R-Sandy. “It should be a program where states and federal government get together and craft a program that will work in each individual state.”

Yet it remains unclear if even Trump’s CMS will approve one key provision Utah is proposing. The HB472 plan calls for only a partial expansion of Medicaid coverage for adults making up to 100 percent of the poverty line, or $12,140 annually for a single person.

The ACA, meanwhile, mandated that states expand their Medicaid programs to cover those making as much as 138 percent of the poverty line. CMS recently declined to approve a similar request by Arkansas, which wanted to cover only residents making 100 percent of poverty incomes.

But both House Speaker Greg Hughes, R-Draper, and HB472’s sponsor, Rep. Robert Spendlove, R-Sandy, said Tuesday they were hopeful Utah’s request would look more appealing to federal officials. Utah, they said, wants to grow its Medicaid coverage, while Arkansas — which had previously approved a full Medicaid expansion under the ACA — was looking to boot people off coverage by changing its income threshold.

“Our request is to expand coverage, while their request is to lower coverage,” Spendlove said.

And if the feds decline to approve any portion of Utah’s Medicaid waiver request, HB472 would require further consideration by Herbert and legislators. “It’s a package deal,” Hughes said.

“Is it everyone’s perfect? It isn’t,” he said the expansion. “Is it good? Absolutely.”

Pamela Atkinson, a Utah homeless advocate, as well as Bill Tibbitts, associate director of the Crossroads Urban Center, were in attendance Tuesday and supported the measure. They have said it would help low-income Utahns get back on their feet.

But others argue it doesn’t go far enough. Officials with the nonprofit Utah Health Policy Project have said Utah’s work requirement and spending caps could result in some impoverished Utahns, who should qualify for coverage, being left out.

At the same time, Utah’s Medicaid ballot initiative — if it passes in November — would expand Medicaid to those making 138 percent of poverty income levels, or 150,000 more people than are covered currently. Organizers of that initiative continue to collect the necessary 113,000 signatures to qualify for the ballot ahead of an April 15 deadline.

Launched last year, backers of the effort say it reflected years of frustration over the Legislature’s failure to pass an expansion. Polls suggest nearly two-thirds of Utahns support expanding Medicaid.

HB472 will soon be the focus of a 30-day public comment period and two public meetings for input before Utah submits its Medicaid expansion request, said Nathan Checketts, director of Utah’s Division of Medicaid and Health Financing.

Officials expect it will be at least six to nine months before CMS issues its decision on the waiver. And it could be several months beyond that — into 2019 — before Utah is prepared to enroll tens of thousands of new Medicaid recipients.

Checketts said he spoke with CMS leaders about Utah’s proposal last week. “We walked them through it and said, ‘Here’s what the bill does,’” he said. “They really appreciated the call, and said those are all policy issues they are going to be looking at.”

But the feds did not give any commitments on whether they would approve Utah’s request, Checketts said, or how long they might take to decide.