Most state legislatures are opening for business this month, and that means that Medicaid expansion is once again becoming a hot issue. The last year has seen a number of Republican-led states start to bend on the program, and the new legislative sessions offer new opportunities to make headways in red America — but could also put one pioneering state at risk.

Four or more conservative mainstays could expand Medicaid in the next year, while another state might become the first to back out of the program after first adopting it. Here’s what you need to know.

WYOMING

Medicaid expansion has been in the works in Wyoming, as solidly conservative a state as there is, since last summer when Gov. Matt Mead (R) started negotiating with the Obama administration. Those talks turned into a formal recommendation from a state task force, and Mead aggressively advocated for expanding Medicaid in his State of the State address last week.

Wyoming’s plan would likely require small co-payments and monthly premiums for enrollees. About 17,000 low-income Wyomingites would be covered by Medicaid expansion.

IDAHO

Despite being led by Republicans, Idaho has already shown an openness to participating in Obamacare: It was the first all-red state to establish its own state-run insurance exchange. Now Gov. Butch Otter is urging state lawmakers to have a debate over Medicaid expansion. Otter hasn’t been as forceful as his neighbor Mead, but said he largely endorses recommendations put forward by a work group last year.

That plan would use traditional Medicaid to cover people below the poverty line and private insurance paid for with Medicaid dollars to cover those above it. About 55,000 low-income Idahoans would gain coverage if the state joined the program.

MONTANA

The Rocky Mountain region looks like Obamacare’s best chance to make headway during 2015. Democratic Gov. Steve Bullock, who is working with a Republicanl-led legislature, put out his Medicaid expansion plan on Monday, according to the Great Falls Tribune. GOP lawmakers have previously rejected expansion proposals and are mulling their own alternative that would not rely on federal Medicaid money.

Bullock’s plan would use private Medicaid managed care companies for the expansion population. It would also create a trigger to cancel the program if the federal government fails to keep its funding pledge (never less than 90 percent), which has been a concern among conservative legislators. About 40,000 people would be covered by Medicaid expansion in Montana.

BIG WILD CARDS: FLORIDA AND TEXAS

Those mountain states would be victories for the Obama administration, which has been increasingly flexible in accommodating conservative alternative plans, but the biggest gets left are Texas (more than 1 million would be covered by Medicaid expansion) and Florida (765,000).

As TPM reported, Medicaid expansion advocates in Texas have been a little more optimistic that new Gov. Greg Abbott (R) might be willing to listen to some kind of expansion compromise. Abbott’s office, however, has pushed back against those reports.

Likewise in Florida, there have been sunnier headlines — “Support builds for Medicaid expansion in Florida,” the Miami Herald said. Business groups have put forward various proposals, according to the Tampa Tribune, such as having enrollees pay small premiums or buy private coverage off an exchange.

ARKANSAS

While the above represent opportunities for Medicaid expansion gains, the program could again be at risk in Arkansas, which has thus far been a trendsetter. Its use of Medicaid dollars to pay for private coverage has been emulated by several conservative states since.

But Arkansas’s program must be re-approved by three-fourths of the state legislature every year. The so-called private option barely survived last year, after hectic horse-trading and the guiding hand of Democratic Gov. Mike Beebe.

Now Republican Asas Hutchinson is governor and new conservative lawmakers have taken office after running against Obamacare. Recent reports suggest that the private option will face significant opposition once again, and the best-case scenario might be renewal with new conservative policies — such as a work-search requirement, which the Obama administration has thus far rejected when proposed elsewhere — tacked onto it.

More than 200,000 Arkansans are currently covered by the state’s Medicaid expansion program.