Philadelphia commissioners signed a letter Monday night, certifying the city's election results to the Department of State.
The Trump campaign had challenged the more than 8,300 mail-in ballots in Philadelphia because of minor technical errors.
The state Supreme Court on Monday those ballots should be counted however.
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A voter’s failure to include a handwritten name, address or date by their declaration on the outer envelope, the court said, does not “warrant the wholesale disenfranchisement of thousands of Pennsylvania voters.”
Other county election boards across Pennsylvania faced a deadline Monday to certify election results to the Department of State, an important milestone in the tabulation of votes for the presidential contest and other races.
A Department of State spokesperson declined to say which other counties have reported, and it was unclear whether an update would be issued at day's end.
“The Department of State continues to work closely with and support all 67 counties as they work to complete the election certification process,” spokesperson Wanda Murren said in Monday morning email to reporters.
The boards in two populous counties split along party lines in votes taken Monday, with majority Democrats in both places voting to certify the results.
Allegheny County, which gave a majority to Democrat Joe Biden, voted 2-1, and Luzerne County, which Republican Donald Trump won, approved its results, 3-2. Messages seeking comment were left for Republicans who voted no in both counties.
Several other counties voted unanimously to certify on Monday, as Erie County did late last week, and there were no reports of counties voting against certification.
Nicole Ziccarelli, a Republican state Senate challenger in Allegheny County, wanted to keep votes without a handwritten date from counting. Ziccarelli is down in AP's count by a single vote, out of about 133,000 cast, against Democratic Sen. Jim Brewster.
Although all seven justices agreed that handwritten names and street addresses on the outer envelopes are not mandatory, just threesaid the date definitely is not required. Three others, a Democrat and both Republicans, would have required the date.
The seventh justice, Democrat David Wecht, said that the date is clearly required but that it may not have been clear to voters, so in this election, ballots inside an envelope without a date should count.
Wecht wrote that he would not enforce the date requirement this year but considers it mandatory for future elections.
After the counties send certified results to Secretary of State Kathy Boockvar, she must then tabulate, compute and canvass votes for all races. The law requires her to perform that task quickly but does not set a specific deadline.
Boockvar then will inform Democratic Gov. Tom Wolf of the results, and he will list the state's electors for the Dec. 14 Electoral College meeting on a “certificate of ascertainment” sent to the national archivist. Four years ago, Wolf made that notification Dec. 12.
Biden won the presidency with the help of Pennsylvania's 20 electoral votes. His margin in the state currently stands at more than 81,000 out of nearly 7 million cast.
Trump’s federal lawsuit challenging the results was dismissed Saturday by a judge who declined to halt Boockvar’s certification. The Trump campaign has appealed to the Philadelphia-based 3rd U.S. Circuit Court of Appeals.
The large number of votes cast by mail, and the large number of provisional ballots that were cast, have been a challenge for vote counters across the state.
In Berks County, which includes Reading, officials do not expect to report to Boockvar until Wednesday, because that is when a five-working day review period will close.
Monday was also a deadline under state law for legal challenges to contest any election to be filed.
In 2016, Green Party candidate Jill Stein moved toward seeking a recount after Trump beat Democrat Hillary Clinton by about 44,000 votes, but Stein ended that effort.