Joe Biden came out swinging at Donald Trump at the weekend, accusing the president of spreading “flat-out lies” with a conspiracy theory about his son that is at the heart of the impeachment inquiry.
“He is frantically pushing flat-out lies, debunked conspiracy theories and smears against me and my family, no doubt hoping to undermine my candidacy for the presidency,” the former vice-president wrote in the Washington Post.
Mr Biden was responding after Mr Trump urged Beijing to find dirt on his son Hunter Biden’s business dealings in China — mirroring a request to his Ukrainian counterpart in the fateful July 25 phone call that sparked the “Ukrainegate” investigation on Capitol Hill.
Mr Trump claims that Mr Biden pushed Ukraine to fire a top prosecutor who was investigating a Ukrainian gas company, Burisma, on whose board Hunter Biden sat. US, European and other international officials have all dismissed the charges as a debunked conspiracy.
However, Mr Biden faces a conundrum. He does not want to fuel the claims by responding blow by blow. But he knows that not rebutting the charges could be dangerous, given how Hillary Clinton seemed to suffer by not defending herself more forcefully in the 2016 presidential campaign.
A Biden adviser said the campaign was being “incredibly aggressive” in responding to the charges in the media, precisely because of the way the 2016 race had unfolded.
“We are aware of how the media covered a lot of the 2016 Hillary storyline that resulted in an unhelpful false equivalence, and we are determined not to let that happen.”
He said one silver lining was that Mr Biden was getting much more media coverage than his Democratic rivals. “It elevates vice-president Biden in a way that makes him the primary protagonist and sucks up a lot of oxygen in the room.”
But the attacks come at a pivotal moment, as Mr Biden, 76, starts to look vulnerable. After holding a sizeable lead in the polls of likely Democratic primary voters, he has suddenly found senator Elizabeth Warren on his shoulder. And the recent hospitalisation of Bernie Sanders after the 78-year-old Vermont senator had a heart attack, has reignited questions about Mr Biden’s age.
According to an average of recent national polls compiled by Real Clear Politics, Mr Biden leads Ms Warren by 26 to 24 per cent. But she has overtaken him in the last two national polls, and has the overall lead in Iowa. She is also gradually making ground in South Carolina, an early voting state where he has his biggest lead, and is tantalisingly close in California.
The Biden adviser said he had his second-best fundraising haul in the week the CIA whistleblower accused Mr Trump of inappropriately pressuring the Ukrainian leader. But he raised only $15m in the third quarter, $9m less than Ms Warren and $10m less than Mr Sanders.
Ed Rendell, a former Pennsylvania governor, urged his friend not to engage on the substance but instead stress that the charges had been debunked. “What Joe Biden should say is that every media outlet that looked at this . . . found no ounce of corruption. The more he talks about it, the more he seems to elevate it on the same level as the charges against Trump.”
In his Washington Post article, Mr Biden did not mention his son by name, or address the allegations. At a recent campaign event in Iowa, he snapped at a Fox News reporter who asked if had spoken to his son about his work in Ukraine.
Pointing his finger at the reporter, Mr Biden said: “You should be asking him the question, why is he on the phone with a foreign leader, trying to intimidate a foreign leader . . . Everybody who has looked at it has said there is nothing there. Ask the right questions!”
But the problem for Mr Biden may be less the conspiracy theory and more the perception that his son may have profited because his father was vice-president. David Ignatius, a Washington Post columnist, wrote that he had shown “poor judgment” in allowing that perception to exist, and that, “Denying this obvious fact only weakens the Democrats’ case against Trump”.
Jonathan Turley, a George Washington University law professor, said that although there was no evidence to support the conspiracy, the other claims had more potential to take hold.
“Few people I know think China and Ukraine looked the world over for an expert on finance and energy issues and came upon Hunter Biden, who just happened to be the son of the vice-president,” said Mr Turley.
Geoff Garin, a Democratic pollster, said it was unclear if the Ukraine affair would hurt or help.
“On the one hand, Biden could use all of this aggressively to confirm that he is the candidate who Trump is most afraid of, to highlight his strength as the most electable candidate,” said Mr Garin. “On the other hand, the constantly repeated descriptions of Hunter Biden’s involvement in Ukraine could raise red flags and worries for Democratic voters.”
The Biden adviser said he thought Mr Biden would be fine but that “anyone who says they know for sure how this will play out is not being truthful because all of this is unprecedented”.
In the meantime, Mr Biden made clear to Mr Trump in his Washington Post article that he would not leave any blows unreturned.
“You won’t destroy me, and you won’t destroy my family. And come November 2020, I intend to beat you like a drum,” he said.
Follow Demetri Sevastopulo and Lauren Fedor on Twitter: @dimi and @laurenfedor