Mr. Roman did not comment for this article.
In a statement, Thea McDonald, a spokeswoman for the Trump campaign, said: “While Democrats have attempted to force rule changes and sow chaos and confusion every step of the way, Republicans have clearly and consistently advocated for stable, understandable rules so that every voter knows how to cast their ballot and can do so with confidence it will count.”
After the June primary, the Republican strategy began in earnest, in a battle that pitted Gov. Tom Wolf, a Democrat, against the Republican-controlled Legislature.
Because of the pandemic, states like Pennsylvania are being flooded with mail-in ballots. Local election administrators and the governor sought to allow early processing of the ballots, known as “pre-canvassing,” but Republicans attached conditions; among them, they wanted to do away with drop boxes, impose new signature-matching requirements and allow poll watchers to cross county lines, a step that good-government groups feared would invite intimidation and delays.
The state has a history of aggressive Republican tactics. In one of the more notorious episodes, Republican poll watchers stationed at a polling place at the University of Pittsburgh in 2004 began challenging the identities of large numbers of students waiting in line to vote, who had to get friends to sign affidavits for them.
Democrats were not seeking to actually scan the ballots early, as many other states are doing. Instead, they simply wanted to allow local officials to get a head start by opening envelopes and flattening the ballots, to get them ready for processing.
“This felt like a layup,” Suzanne Almeida, a lawyer for Common Cause in Pennsylvania, said, adding, “county elections officials and county commissioners were very clear about how critical this was to them.”
But the Republican maneuvers mean even those efforts will have to wait until the morning of Election Day.