Mr. Trump, who also made unfounded claims about fraud in the 2016 election even though he won, has signaled that he will not hesitate to go back to court after Election Day if he does not like the result. Unlike in 2000, when the Justice Department largely stayed on the sidelines, Democrats worry that Mr. Barr will intervene with civil suits, investigations or public statements, casting doubt on the result if Mr. Trump appears to lose. And some Democrats say they are not sure how Mr. Trump would respond, with the presidency on the line, to a court ruling against him.
Some Democrats even express fear that Mr. Trump would send federal agents into the streets as he did in recent weeks in Portland, Ore. Democrats have game-planned situations in which Mr. Trump deploys immigration officers into Hispanic neighborhoods to intimidate citizens shortly before the election and suppress turnout.
“It is very, very much a concern,” said Alex Padilla, the secretary of state of California.
Mr. Trump’s advisers dismiss such talk as overheated partisan messaging. Justin Clark, the president’s deputy campaign manager, said states like California and Nevada trying to expand mail-in voting on the fly were the ones setting the stage for a chaotic election.
“Rushing to implement universal vote-by-mail leads to delays in counts, delays in results and uncertainty about who won an election,” he said.
It took six weeks for the New York authorities to determine the winners of two House Democratic congressional primaries as they struggled with 10 times the normal number of absentee ballots, a case study in the potential for a lengthy count in the fall even if not an example of fraud as Mr. Trump has falsely claimed.
Mr. Clark is one of the party’s top warriors on election fraud fights. In a recording from 2019, he told fellow Republicans: “Traditionally, it’s always been Republicans suppressing votes in places. Let’s start protecting our voters.”
Republicans, he said, should be more aggressive. “Let’s start playing offense a little bit,” he said then. “That’s what you’re going to see in 2020. It’s going to be a much bigger program, a much more aggressive program, a much better-funded program.”