MADISON, Wis. (AP) — There remained no evidence of any wrongdoing, fraud or irregularity in Wisconsin's presidential election on Thursday, as counties worked to wrap up the certification of their votes and their estimates of how much it would cost to recount them, the state's top elections official said.

Democrat Joe Biden defeated President Donald Trump in Wisconsin by about 20,500 votes, based on unofficial results. Trump and his allies have made unsubstantiated claims of wrongdoing, with no evidence, and Republicans in the Legislature have said they planned to launch an investigation into the integrity of the election.

Election results from 55 of Wisconsin’s 72 counties were certified as of Thursday morning, with only marginal net changes to the unofficial results that were reported on election night.

Biden has picked up 43 additional votes while Trump gained 39, giving Biden a net pickup of just four votes. One reason for the changes is the counting of provisional ballots that came in after Election Day, said Meagan Wolfe, the state's top elections official. She said there were 366 provisional ballots issued in the presidential election.

“It’s rare to see any sort of significant changes," Wolfe said. “There's always minor errors. ... We're certainly not seeing anything unusual."

Wolfe defended the integrity of the election, noting all the opportunities the public has to observe the process, including on Election Day, during the county canvass and during any recount that may occur.

“The election process in itself is designed to be transparent,” she said. “It’s designed for people to ask questions and raise concerns every step of the way. ... Everything from the issuance of absentee ballots to voter registration records, those are all publicly observable, available to public scrutiny.”

Because Trump’s margin of defeat is less than one percentage point, he can request a recount. He can’t make that request until the last county canvasses the vote. The deadline is Tuesday and Brown County Clerk Sandy Juno said she didn’t expect to finish until then because the county was thinly staffed due to the coronavirus pandemic.

Trump is also responsible for paying for the recount before it starts. The 2016 recount, which was paid for by Green Party candidate Jill Stein's campaign, cost $2 million. Clerks estimate that costs this year could be higher because of the challenges posed by the pandemic, such as finding larger venues to safely conduct the recount, Wolfe said.

“A pandemic changes a lot when it comes to spacing issues,” Wolfe said.

If Trump requests a recount, as promised, that would start the clock on a series of deadlines to begin and complete the recount. Once it starts, clerks would have 13 calendar days to finish it. Dec. 8 is the deadline for the elections commission to certify the election results if there is a recount.

Any recount is not expected to result in widespread changes to the result. The 2016 presidential recount netted 131 additional votes for Trump, who defeated Democrat Hillary Clinton by fewer than 23,000 votes in Wisconsin.

Thirteen of the 55 counties that had completed their canvasses as of Thursday reported no change in the results. Most counties reported only a handful of changes.

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