Donald Trump has taken to Twitter to again criticise the effort, describing it as "just a Stein scam to raise money"
US Green Party politician Jill Stein has said she will seek federal court intervention in her battle for a recount in the state of Pennsylvania.
She has raised more than $7 million for recounts in Michigan, Pennsylvania and Wisconsin (all states where Donald Trump enjoyed narrow victories) - but legal challenges have been launched in a bid to halt the efforts.
The Stein campaign has now dropped a case in Pennsylvania state demanding a recount - but says it is instead planning to 'escalate' its actions.
In a statement, Jonathan Abady - lead counsel for the Stein recount efforts - explained: "Make no mistake – the Stein campaign will continue to fight for a statewide recount in Pennsylvania. We are committed to this fight to protect the civil and voting rights of all Americans.
"Over the past several days, it has become clear that the barriers to verifying the vote in Pennsylvania are so pervasive and that the state court system is so ill-equipped to address this problem that we must seek federal court intervention. As a result, on Monday the Stein campaign will escalate our campaign in Pennsylvania and file for emergency relief in federal court, demanding a statewide recount on constitutional grounds.”
Ms Stein has also warned that a delay in Michigan "creates a risk that the recount will not end on time. That is unfair to Michiganders".
She has also been highlighting a $1 million bond ordered by the court in Pennsylvania. The Washington Post reports that lawyers have said the campaign cannot afford that amount.
PA voters are worried about the accuracy, security and fairness of an election tainted by suspicion. That's why a $1M bond is outrageous.— Dr. Jill Stein (@DrJillStein) December 4, 2016
Ms Stein has already upped her crowdfunding goals several times in the wake of increasing costs.
Donald Trump, meanwhile, has continued his criticism of the recount efforts, again referring to the process as a 'scam'.
The Green Party just dropped its recount suit in Pennsylvania and is losing votes in Wisconsin recount. Just a Stein scam to raise money!— Donald J. Trump (@realDonaldTrump) December 4, 2016
Calls for recounts intensified after a number of media outlets reported that a prominent computer scientists and election lawyers have been investigating the possibility that electronic voting machines could have been manipulated or hacked.
Marc Elias, counsel for the Clinton campaign, has indicated that the campaign will participate in the recount process - but has stressed they themselves had not uncovered any actionable evidence.
Hillary Clinton’s campaign didn’t want this recount and doesn’t think it will change anything - The Washington Post https://t.co/qmz3hdZd6i— Marc E. Elias (@marceelias) November 29, 2016