CHARLESTON — Expanding Medicaid may help more West Virginians with their heart disease, diabetes and other chronic ailments that are prevalent in the state. But the health care program is already a budgetary burden that threatens to outstrip available state revenues, Gov. Earl Ray Tomblin argued in his letter on the topic last week.

Tomblin outlined the quandary the state faces when he wrote to Health and Human Services Secretary Kathleen Sebelius on Thursday, seeking additional details about the Medicaid provision and other aspects of the recently upheld federal health care law.

The overhaul calls on states to expand Medicaid starting in 2014 to cover people with unadjusted annual household incomes of up to 138 percent of the federal poverty level. That’s around $31,800 for a family of four. West Virginia now restricts the program to households with children at up to 35 percent of the poverty line, or $8,068 for a four-person family.

But in upholding the law in late June, the U.S. Supreme Court also ruled that states that don’t expand coverage cannot lose their existing share of federal funds for Medicaid, as the overhaul had threatened. That finding prompted Tomblin to question Sebelius about federal aid options available if West Virginia, for example, gradually opens up the program, or expands to a lesser income threshold.

“Before a final decision is made, West Virginia must have a plan for the long-term sustainability of any type of Medicaid expansion,” Tomblin said in a statement announcing the letter. “Right now, we don’t have the information necessary to make the decision.”

Tomblin is not alone in weighing options.

Wyoming Gov. Matt Mead also wrote Sebelius on Thursday, quizzing her for more details. The Republican is leaning against expansion after leading his state to join the unsuccessful legal challenge of the law.

“I have grave concerns about the financial impact of expanding Medicaid,” Mead wrote in his letter, which also focuses on the overhaul’s health care exchanges for purchasing insurance coverage.

Arkansas Gov. Mike Beebe, a Democrat, has also sought answers from federal officials. Though Beebe has spoken in favor of heeding the federal law’s call regarding Medicaid, he’s also noted that state lawmakers will ultimately decide the question. In New Mexico, GOP Gov. Susana Martinez fielded a plea from more than 50 groups in her state last week urging in favor of expansion. Those advocates include the New Mexico Pediatric Society and that state’s Conference of Catholic Bishops.

The Republican Governors Association raised numerous questions about expanding Medicaid and other provisions in the new law in a letter to President Barack Obama shortly after the Supreme Court ruled. Republican leaders in at least 10 states have signaled that they will reject or lean toward rejecting the Medicaid expansion. Bill Maloney, Tomblin’s GOP opponent in this year’s election for governor, has indicated he would do the same.

Slamming Tomblin, Maloney criticized the potential cost of the federal health care law in a statement last week and repeated his desire to see it repealed.

“Access to affordable health care is vitally important, but ‘Obamacare’ is not the answer,” Maloney said.

Medicaid covers around 330,000 West Virginians, the 12th largest program among the states when measured against overall populations, according to the latest U.S. Census Bureau figures. The budget that took effect July 1 devotes $860 million in state funds toward Medicaid. Each of those dollars draws down federal funds through a matching rate that’s tied to income levels.

As a result, the state program is budgeted for a little over $3 billion this fiscal year. That’s up from $2.4 billion spent during the 2008-09 budget year, when West Virginia’s share of the funding totaled $540 million, according to figures compiled by the nonpartisan Council of State Governments.

State spending nationally on Medicaid totaled $148.7 billion during the 2010-11 year, the latest available from the council.

 Those figures suggest that 44 other states devoted a larger portion of their general revenue fund toward Medicaid than West Virginia.

Expanding Medicaid under the overhaul would increase the state’s share of costs by an average of $27.3 million annually for the first six years, according to estimates from the nonpartisan Kaiser Commission on Medicaid and the Uninsured. But the federal law would fully cover the state’s share for the first three years, and then offset the increased costs by gradually decreasing amounts. The state’s share for covering those additional enrollees would rise to 10 percent as of 2020.

About 244,000 West Virginians — or about 13.5 percent of the population — are uninsured. The state also ranks high or leads the nation for such chronic health issues as hypertension, heart disease, diabetes and obesity.