It is not clear whether specific fraud is occurring, particularly on the kind of scale that could influence the outcome of the presidential election.
However the Trump campaign has cited limited access to watch vote-counting in Pennsylvania and alleged instances of people who tried to vote in Nevada, being told that they had previously submitted a mail ballot even though they explain they, allegedly, had not done so.
The Trump campaign also has similar complaints about its access to view ballots as they are counted in Michigan, though a judge ruled against the campaign Thursday afternoon. The campaign announced legal action in Pennsylvania, Michigan, Nevada, and elsewhere.
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"All of the recent Biden claims States will be legally challenged by us for Voter Fraud and State Election Fraud. Plenty of proof - just check out the Media," Trump said in a tweet." WE WILL WIN! America First!"
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"STOP THE FRAUD!" the president wrote in another.
The Biden campaign, meanwhile, has called Trump's legal efforts "pathetic."
"What makes these charades especially pathetic is that while Trump is demanding recounts in places he has already lost, he's simultaneously engaged in fruitless attempts to halt the counting of votes in other states in which he's on the road to defeat," Biden spokesman Andrew Bates said. "This is not the behavior of a winning campaign. Plain and simple, Donald Trump has lost Wisconsin, he is losing Michigan, and he is losing the presidency."
There is also another legal challenge brewing from the Pennsylvania Republican Party, which the Trump campaign has asked to join, against a ruling by the Pennsylvania Supreme Court that ballots cast by Election Day but received up to three days later may be counted anyway
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The Trump campaign succeeded in one legal challenge in Pennsylvania, however, in which it claimed that its observers were not being allowed close enough to watch mail ballots be counted in Philadelphia.
Trump said it was a "Big legal win in Pennsylvania!"
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The Trump campaign, however, has said the city is not complying with the appeals court ruling. Meanwhile, Philadelphia appealed the appeals court ruling to the Pennsylvania Supreme Court.
Still, it's not clear that there are specific instances of fraud or inconsistencies in Philadelphia, but Trump representatives argue that they are not being allowed close enough to poll workers to tell whether or not there are any.
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A statement from Trump, emailed by his presidential campaign, makes clear that he believes that instances of fraud that are discovered will be widespread enough to affect the outcome of any state one way or another.
"IF YOU COUNT THE LEGAL VOTES, I EASILY WIN THE ELECTION!" the president stated. "IF YOU COUNT THE ILLEGAL AND LATE VOTES, THEY CAN STEAL THE ELECTION FROM US!"
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