DETROIT — Mayor Mike Duggan on Wednesday accused President Trump’s allies in Michigan’s most populous county of racism after they threatened to block certification of the election over slight discrepancies in majority-Black precincts — while ignoring similar problems in heavily white areas.
The complaint echoed accusations against Mr. Trump and his allies around the country — charging Republicans with preying on ugly racist stereotypes to cast doubt on Black voters in their last-ditch effort to overturn a legitimate election Mr. Trump lost decisively.
On Tuesday night, Republican election board members in Wayne County, which contains Detroit and its inner suburbs, refused to certify the county’s election results in a nakedly partisan effort to hold up President-elect Joseph R. Biden Jr.’s victory over Mr. Trump.
Hours later, they reversed themselves after an outcry from state officials and Detroit residents who accused them of trying to steal their votes.
“You could see the racism in the behavior last night,” Mr. Duggan said at a news conference Wednesday. “American democracy cracked last night, but it didn’t break. But we are seeing a real threat to everything we believe in.”
The Rev. Wendell Anthony, the head of Detroit’s N.A.A.C.P. chapter, said the Trump campaign’s attempts to discredit the election in cities with large Black populations like Detroit, Philadelphia and Atlanta fit a racist pattern of stoking divisions and undermining democratic institutions.
“We are not going to let them steal the election right before our eyes,” said Mr. Anthony, who helped quickly organize a protest Tuesday night to push the Republican board members to reverse their votes.
The two Republican members of the Board of Canvassers in Wayne County, which voted overwhelmingly for Mr. Biden, are white. The Republicans, Monica Palmer and William Hartmann, said they were voting against certifying the results because precincts in the county had conflicting figures for the numbers of votes cast and the number of voters recorded as having participated, even though the disparities mostly involved small numbers of votes.
At one point, Ms. Palmer moved to “certify the results in the communities other than the city of Detroit.”
Mr. Biden won nearly 95 percent of the vote in Detroit, which is more than three-quarters Black. The rest of Wayne County, which voted for Mr. Biden by a smaller margin, is more than three-quarters white.
Ms. Palmer’s motion drew cries of outrage at the meeting, which was held over Zoom.
A Black Detroit resident who attended the meeting, Benita Bradley, asked the Republicans, “Do you know how many young Black teenagers voted for the first time this year? And you sit here and slap those people in the face.”
The board’s initial 2-2 deadlock was among the starkest examples of how previously routine aspects of the nation’s voting system have been tainted by Mr. Trump’s monthslong effort to undermine confidence in the election.
One of the two Democratic members of the board, Jonathan Kinloch, who is Black, said that after the initial vote, he spoke to Ms. Palmer for more than half an hour to try and convince her that certifying the results was the right thing to do and trying to find a way to reach a compromise.
“When it comes to elections, white people don’t understand how ingrained the right to vote is in our conscience,” Mr. Kinloch said. “All those barriers that our grandparents had to do in order to exercise their right to vote that is so easily available to whites in America.”
Neither Republican board member responded to a request for comment on how they came to change their votes.
The office of the Michigan secretary of state, Jocelyn Benson, wrote on Twitter Wednesday that “all counties have certified their election results” and that the state’s canvassing board would meet next Monday to certify the election. Mr. Biden beat Mr. Trump in Michigan by nearly 150,000 votes.