The Georgia State Election Board on Friday voted 3-2 to require counties to hand-count ballots cast on Election Day, a move that could drastically lengthen the amount of time to tally results in a critical battleground state.

The move, which will require poll workers to open up ballot boxes and count the number of ballots by hand at the end of the night, was approved by three board members who've been praised by former President Donald Trump, and was opposed by Democrats in the state, as well as by the Republican secretary of state and attorney general.

“I want to make on the record that we’ll be going against the advice of our legal counsel by voting in the affirmative,” the Georgia election board's chair, John Fervier, said before the motion passed. Fervier, who was appointed by Georgia GOP Gov. Brian Kemp, and Sara Tindall Ghazal, the lone Democratic appointee on the panel, voted against the new rules.

Secretary of State Brad Raffensperger had previously warned the new rule could cause "chaos."

“We consider these major changes to the election process,” Raffensperger told NBC News on Thursday. “I guess we have several concerns. Number one is the actual counting of the number of ballots that you have at the precinct. That’s going to take time. Everything that we’ve done for the last six years has to speed up the process to give the voters the results quicker, and all of a sudden now they’re adding an element that it’s actually going to take longer.”

In a statement after Friday's vote, Raffensperger said, “Attorney General Chris Carr has stated that these rules would not withstand a legal challenge, and I have worked every day to strengthen Georgia’s election law to ensure our elections remain safe, secure, and free.”

In a letter to the board Friday ahead of the vote, Senior Assistant Attorney General Elizabeth Young said her office doesn’t typically weigh in on amendments to election administration, but was making an exception because "the proposed rules, if passed, very likely exceed the Board’s statutory authority and in some instances appear to conflict with the statutes governing the conduct of elections."

She also argued, “As a general matter, the passage of any rules concerning the conduct of elections are disfavored when implemented as close to an election as the rules on the September 20 agenda.”

One of the board members who voted in favor of the new rule, Janelle King, suggested Raffensperger’s concerns were overblown.

“I do not have those concerns at all,” King told NBC News.

“I think it’s actually going to be the reverse,” she said, because “we won’t have a situation where we have any candidates saying that they think the count is off or they want an audit because something went wrong. We would have caught it at an early stage.”

Hand-counting ballots has captured the attention of many on the right in recent years in response to baseless claims about hacked voting machines, despite ample evidence that counting by hand is more expensive and less accurate than using ballot tabulators.

Last year, officials in Mohave County, Arizona, tested out hand-counting the votes. They found it took staffers three minutes to count a single ballot, and that the staffers made routine errors.

Georgia's rule only requires election workers to count the number of ballots — not every vote on the ballot — but election officials are still worried about the impact.

Charlotte Sosebee, the elections director in Clarke County, Georgia, said counting ballots late at night could pose unforeseen problems, such as poll workers not agreeing on the number of ballots during a count.

"If we do this, are they really going to trust the process? I mean, what's next?" she told NBC News.

Anticipating that the rule would pass, Sosebee said she had already trained her poll workers on it. But the additional working hours needed to pay the poll workers wasn't in the budget, so the county needs to spend more to cover the costs.

In August, the same Georgia board members passed other new rules that would allow county election board members to conduct “reasonable” inquiries before they certify results. Critics say that could throw the election into chaos because “reasonable inquiry” isn’t defined, and an individual board member could block certification for any reason.

The Democratic National Committee, the Democratic Party of Georgia and several individuals filed suit challenging those rules last month.

Speaking of the trio of board members who voted for them at a rally last month, Trump said, “They’re on fire. They’re doing a great job.”

“Janice Johnston, Rick Jeffares and Janelle King, three people are all pit bulls fighting for honesty, transparency and victory,” he said then.