JUNEAU -- While a new poll says Alaskans strongly favor Medicaid expansion, legislative opponents continue to maneuver to stop Gov. Bill Walker from accepting it over their objections.

And they're not even officially acknowledging that Walker has the authority to accept expansion without their concurrence.

Sen. Pete Kelly, R-Fairbanks, Thursday amended the state's operating budget to include a prohibition on accepting money for Medicaid.

"We want to make sure that it can't be done unilaterally by one branch of government," Kelly told the Senate Finance Committee as it passed a series of budget amendments Thursday.

Walker has appeared to suggest that he has the authority to expand Medicaid on his own, though he also complied with legislators' demands that he introduce a bill specifically to do so. Walker spokesperson Grace Jang declined to say whether Walker believed he had that authority.

"That's not the governor's preference," she said.

Medicaid expansion would bring medical coverage to thousands of low-income, uninsured Alaskans who currently don't qualify because they don't have children or lack other factors. Nearly all expansion costs would be paid by the federal government.

The Legislature might not be able to block expansion, Kelly told reporters later, even while maintaining that Walker didn't have the authority to do so on his own.

"I don't think he has the authority, unless we give it to him," Kelly said.

The Alaska House also attempted to write a ban on Medicaid expansion into its budget, but Kelly said the Senate's language is stronger and more likely to succeed. Because the two budgets are different, they'll have to be reconciled in conference committee.

But Kelly went on to say that either chamber's attempt to block a Walker Medicaid expansion might fail.

"I couldn't even tell you this is going to work, but the fact is that we have to establish our position if we don't want him to act unilaterally to bypass the appropriation process," he said.

The Senate debate came as the House released a poll showing nearly 2-1 support for Medicaid expansion among Alaskans.

Sixty percent of those polled supported expansion, while 31 percent were opposed, according to the poll by Dittman Research. Of those, 37 percent strongly supported, while only 18 percent were strongly opposed.

House Speaker Mike Chenault said that most legislators were unlikely to be swayed by the poll.

"Nobody's come to me and said 'Hey Mike, since the poll showed Alaskans are in favor, I favor it now,' " he said.

Lawmakers already tend to have firm positions on the issue, no matter which side that is, he said.

"I don't think the poll changed anyone, whether they're going to vote yes or no," Chenault said.

Chenault and Kelly said the state's Medicaid system needs reforms. They said they might accept expansion if they can reach agreement with the Walker administration on reforms and include them in the expansion bill.

The poll also found some expected results, such as unhappiness with President Barack Obama, the federal government and restrictions on oil and gas development in ANWR.

While the poll found Alaskans had positive feelings about both Gov. Walker and the Alaska Legislature -- Walker at 54 percent and the Legislature at 52 percent -- the new governor's negatives were only 13 percent while the Legislature's were 34 percent, with many more Alaskans unsure about Walker than the Legislature.

The Dittman poll surveyed 700 Alaskans, and had a margin of error of just under 4 percent.