Shortly before Gov. Roy Cooper, a North Carolina Democrat, began his first term in 2017, his rivals in the Republican-controlled legislature voted to strip the position of key powers, including the governor’s longstanding authority to appoint majorities to the state election board and local election boards in all 100 counties. After the state Supreme Court ruled that move illegal, the lawmakers put the idea on the ballot, but the state’s voters shot that down, too.

Now, seven years after their first try, the legislators appear on the verge of getting what they have long sought.

On Wednesday, the State House of Representatives followed the State Senate in passing legislation that would put the legislature in charge of all election board appointments. It would also change the number of positions on each board to split seats equally between Republican and Democratic members, eliminating the extra seat — controlled by the governor — that had served as a tiebreaker in disputes.

Under the newly passed bill, ties in local election boards would be addressed by the State Board of Elections — which, under the bill, would also have an equal number of members from each party.

Republicans still have to meld the House and Senate versions into a single measure and then override a certain veto by Governor Cooper. Neither appears to pose a problem, particularly after a Charlotte-area state representative defected from Democratic ranks to the Republican Party last spring, giving it a veto-proof majority in both houses of the legislature.

Another court challenge is likely. But it probably will end up before a state Supreme Court controlled by Republicans who have established a pattern of reversing past Democratic rulings in politically sensitive cases.

Well beyond any policy differences, the Republicans’ move to shift power from Governor Cooper to themselves underscores the blood-feud intensity of the political divide in a state evenly split between Republican and Democratic voters but where Republicans increasingly have gained political control.

Since they took control of the legislature in 2011, Republicans have sought to entrench their power through gerrymanders and legal gambits, saying that Democrats also made use of gerrymanders when they held control.

The majority also raised eyebrows this week by inserting a clause in budget legislation that would exempt all legislators from complying with the state open records law or other mandated disclosures. The move came days before Republicans kick off the process of drawing new political maps that appear all but certain to expand their control of the legislature; current law requires that redistricting documents be made public.

Another clause — this one tucked into the election legislation — would accelerate legislative appointments to the state Environmental Management Commission, handing Republicans control of the body. The commission soon will consider rewritten wetland rules and complete a mandated review of all state environmental regulations, The Raleigh News & Observer reported.

“It’s a power grab by the majority,” State Senator Dan Blue, a Democrat and the chamber’s minority leader, said of the elections legislation. “There’s nothing unusual about what autocrats try to do once they get control. They try to keep it.”

Not so, said State Senator Warren Daniel, one of the Republican sponsors of the election bill. “This is about taking away a power grab” by governors of both parties, he said. “We think it’s time to take party politics out of the administration of elections.”

A pivotal question is whether the legislation passed on Wednesday would actually do that, or would in fact achieve the opposite.

Despite its partisan nature, the existing system that gives a governor nominal control over the makeup of election boards has worked without controversy under governors of both parties for decades.

Mr. Daniel and other Republicans nevertheless call the House measure a common-sense move to scrub partisanship from election boards and promote compromise on thorny election issues.

Democrats and voting-rights advocates argue that the legislation would encourage the opposite. The equally divided boards, they said, would allow Republicans to use tie votes to block adoption of some measures, such as allotting early-voting polling places in solidly Democratic cities, that might impede Republican success.

The legislation “will leave us with county and state boards that can gridlock,” said Ann Webb, the policy director for Common Cause North Carolina, which opposes the measures. “And in this political environment of hyperpartisanship, we fully expect that they will gridlock.”

A former state Republican Party official who said he supported the bipartisan boards, Dallas Woodhouse, said warnings that boards would block access to the polls were “fear mongering.”

“Republicans didn’t do that when they controlled the election boards under McCrory,” he said, referring to Governor Cooper’s Republican predecessor, Pat McCrory. “Why would it happen under this?”

Ms. Webb and other critics say their concerns might have been allayed had the legislature added language to the House bill that laid out instructions to break deadlocks. But “those suggestions have been rejected,” she said.

Experts say it is hard to tell whether fears over gridlocks are well-founded.

“In general, the overwhelming majority of county election board members want to do things in a nonpartisan manner,” J. Michael Bitzer, an expert on North Carolina politics at Catawba College, said.

That is in part because local politicians generally have chosen who sits on county election boards, a mostly thankless job that many party loyalists decline. Whether that will change when the legislature chooses board members, he said, is an open question.

“I think a lot of the doomsaying about bipartisan boards is overblown,” said Andy Jackson, who directs the Civitas Center for Public Integrity at the conservative John Locke Foundation. “But we’ll see what happens.”

But election behavior from the past is not necessarily a guide for what happens going forward.

Ms. Webb said critics’ concerns go beyond squabbles over polling places to the very basics of the election process, especially in presidential politics.

Already she said, some local election officials in the state initially refused to certify the results of the 2022 midterm elections because they mistrusted election procedures. It fell to local boards to address the issue.

If that becomes a partisan question in 2024, she said, “we’re going to see what will feel very much to voters like chaos, and very well could be that.”