Former national security adviser Michael Flynn—controversially pardoned by President Donald Trump last week—on Tuesday retweeted a call for the White House to declare martial law and re-run last month's presidential election.

The appeal—made by the Ohio non-profit We The People Convention in a Washington Times advert Tuesday—urged the president to declare "limited martial law" in order to hold a new election.

The advert cited President Abraham Lincoln's suspension of Habeas Corpus during the Civil War as precedent, adding: "Then, as now, a President with courage and determination was needed to preserve the Union."

WTPC claimed the "threat to our United States by the international and domestic socialist/communist left is much more serious than anything Lincoln or our nation has faced in its history—including the civil war."

The organization's President Tom Zawistowski released a statement claiming "massive, planned, illegal election fraud conducted by corrupt Democrat/Socialist Party operatives across our nation to steal our vote."

But WTPC provided no evidence to support its claims, which have been debunked by bipartisan election officials and Trump's own Justice Department.

The retired general Flynn tweeted a link to the appeal, writing alongside it: "Freedom never kneels except for God."

Flynn received a presidential pardon last week for his conviction for lying to the FBI about his contacts with Russia in 2017.

The broad pardon also applied to any possible crimes he might have committed connected to special counsel Robert Mueller's probe of Russian interference in the 2016 election.

His pardon has become a cause célèbre for Trump supporters, who consider him a victim of President Barack Obama's administration's supposed efforts to spy on and undermine the Trump presidential campaign.

This conspiracy theory has also been widely debunked.

Flynn has also become a hero among proponents of the QAnon conspiracy theory, which claims Trump is at war with a shadowy cabal of powerful international pedophiles.

Trump, his campaign and allies have maintained that he was cheated out of last month's presidential election by a sophisticated campaign of electoral fraud.

The president and his lawyers have failed to provide any evidence to support the assertion, and Attorney General Bill Barr said Tuesday the Justice Department had found no evidence of fraud that would have affected the result.

But Trump plus some of his allies and supporters have spread the conspiracy theory regardless.

QAnon followers, online extremists and fringe groups like WTPC have proved fertile ground for the baseless claims of electoral fraud, helping create an alternative narrative in conservative media and on social media that experts have warned could encourage real-life violence.

Talk of martial law, armed resistance to stop the supposed anti-Trump "coup" and calls for a second Civil War are common on platforms including Facebook, Twitter and Parler.

Partisan rhetoric is growing increasingly aggressive as the transition to President-elect Joe Biden's inauguration on January 20.

Trump lawyer Joe DiGenova, for example, said Monday that former head of U.S. election security Chris Krebs should be "taken out at dawn and shot" for saying that Trump's defeat was not a result of voter fraud.

The president fired Krebs after he refused to support the election conspiracy theory. Krebs has remained defiant, and wrote in a Washington Post op-ed published Tuesday: "The 2020 election was the most secure in U.S. history."

President Donald Trump’s former national security adviser Michael Flynn leaves the E. Barrett Prettyman U.S. Courthouse on June 24, 2019 in Washington, D.C.Alex Wroblewski/Getty Images/Getty