The legal challenge is the latest attempt by Republicans to invalidate the 2019 law that Republican lawmakers almost unanimously supported.
Gov. Tom Wolf vetoed a Republican-crafted elections bill that would have mandated voter identification in all elections.
Republicans passed an election bill that restricts voter access, but Gov. Tom Wolf will veto it.
Republicans have proposed a wide-ranging series of changes to Pennsylvania election laws, including many that would make it more difficult to vote.
As the Republican-controlled Pennsylvania Legislature works to pass voter suppression laws, Democrats in Congress have one chance to stop the assault on voting rights.
“They have failed to allege that even a single mail-in ballot was fraudulently cast or counted,” one judge wrote.
“The Court must be flexible in favor of the right to vote,” the judge said.