Meanwhile, Republican lawmakers in Pennsylvania held a hearing on accusations of rampant fraud and irregularities in the vote-counting.

"All that we ask is that you listen to the facts we are presenting and then evaluate it," said Rudolph W. Giuliani, the lead lawyer for the Trump campaign legal team. "We don't want to disenfranchise anyone."

Mr. Giuliani presented witnesses who said that, despite their jobs as designated Republican poll watchers, they were prevented from inspecting mail-in ballots in Philadelphia, Pittsburgh and elsewhere in the state.

More than 670,000 ballots lacked proper inspection and should be tossed, according to the Trump campaign.