After Joe Biden’s big Super Tuesday wins, it’s obvious that he’s the Democratic frontrunner. And all of a sudden, Republicans are talking about Hunter Biden and Ukraine again — with Senate Homeland Security Chair Ron Johnson (R-WI) telling reporters on Wednesday that he plans to issue some kind of report on the matter in the coming months.

“These are questions that Joe Biden has not adequately answered,” Johnson said, per Politico. “And if I were a Democrat primary voter, I’d want these questions satisfactorily answered before I cast my final vote.”

The Democratic elite has unified around Biden largely on the grounds of electability, that he’s more likely than chief rival Bernie Sanders to beat Trump in the general election. But Johnson’s comments underscore that Biden might not be nearly as safe on that front as either Democratic officials or voters think. They’re risking setting themselves up for a fall campaign mired in scandal and innuendo — a 2020 version of “Her Emails” that plays right into Trump’s “drain the swamp” narrative.

The Ukraine situation centered on the younger Biden’s position on the board of Burisma, a Ukrainian energy company. While Hunter was on the board, Biden was vice president — and was attempting to pressure Ukraine’s government to fire a prosecutor general, Viktor Shokin, who was widely seen as impeding anti-corruption efforts. Trump has tried to spin these two events into some kind of scandal in which the elder Biden was working to protect the company that employed his son from a crusading prosecutor.

Trump’s allegation is obviously false and deeply ironic, given that the president himself got impeached for improperly pressuring the Ukrainian government to investigate Biden over this issue. But the mere fact that there’s no actual scandal here doesn’t mean the perception of one won’t hurt Biden.

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One of Trump’s chief political talents is attracting extraordinary amounts of credulous media attention to his bizarre theories, in ways that end up creating a stench of corruption around his opponents. One of Biden’s central rationales for running against Trump is restoring dignity and honor to the White House, an argument that could be undermined in the public’s eye by even the whiff of scandal. Hillary’s emails were a fake problem too — right up until they torpedoed 2016’s “safer than Bernie” choice.

Sanders certainly has electability problems, most notably turning off moderates who might be willing to vote for a less extreme not-Trump. But it’s just not obvious that Biden is the clearly safer choice, especially given what we saw four years ago. He may not be uniquely risky compared to the rest of the field, but it’s also not clear that he’s as electable as most Democrats seem to think he is.

The party needs to grapple with this openly before concluding that he’s their only option.

What really happened with the Bidens and Ukraine

The Hunter Biden situation involves a lot of names from mid-2010s Ukrainian politics that you, dear reader, may be forgiven for not remembering. Luckily, my colleague Matt Yglesias has a very helpful guide to it. Here’s the key background:

Back in 2014 after a change of regime in Ukraine, Hunter Biden joined the board of a scandal-plagued Ukrainian natural gas company named Burisma. Hunter had no apparent qualifications for the job except that his father was the vice president and involved in the Obama administration’s Ukraine policy. He got paid up to $50,000 per month for the job and the situation constituted the kind of conflict of interest that was normally considered inappropriate in Washington until the Trump era. These days, of course, the president of the United States regularly accepts payments from foreign sources to his company while in office, and so do the Trump children. The Obama administration probably should have done something about this at the time, but the White House couldn’t literally force Hunter not to accept the job. And given the larger family context, you can see why Joe might have been reluctant to confront his son about it. This would all be a small footnote in history except that by 2016, officials throughout the Obama administration and in Western Europe had come to a consensus that Ukraine’s prosecutor general, Viktor Shokin, wasn’t doing enough to crack down on corruption. Biden, as he later colorfully recounted, delivered the message that the West wanted Shokin gone or else loan guarantees would be held up, and Shokin was, in turn, fired. There was nothing remotely controversial about this at the time. No congressional Republicans complained about it, and the European Union hailed the decision to fire Shokin. The reason there is video footage of Biden touting his personal role in this is it was considered a foreign policy triumph that Biden wanted to claim credit for, not anything sordid or embarrassing. But Shokin, of course, didn’t want to go down on the theory that he was corrupt or incompetent. So he started offering another theory: he was fired for going after Burisma by Joe Biden operating on behalf of Hunter Biden.

There are two conclusions to draw from this set of facts.

First, Hunter Biden got his job with Burisma because he was Joe Biden’s son. This is both a troubling statement about the elite-driven corruption of capitalism and meritocracy as well as a window into Biden’s political liabilities. Trump’s self-dealing and nepotism are obvious weak points, but he can parry Biden’s attacks on that front by citing Hunter.

Second, Joe Biden’s conduct toward Shokin had nothing to do with his son — and everyone at the time knew it. The only person saying otherwise was Shokin, who seems to quite obviously have been lying to preserve his own reputation.

Trump’s allegation of wrongdoing by Biden is merely a warmed-over version of Shokin’s self-interested complaint. It’s obviously, risibly false.

But electorally speaking, it’s far from clear how much that matters.

The case for worrying about Biden’s electability

Trump’s various claims about Clinton’s use of a private mail server were absurd. Yet that didn’t stop mainstream media from obsessing over them.

Part of the problem is the entrenched commitment to portraying “both sides” of a story among mainstream media reporters. Another is the inherent limitations of cable news and traditional news article, which are ill-suited for conveying complex realities. Some reporters have even, at times, seem genuinely convinced that there’s some scandal in Biden’s behavior.

For all these reasons, it’s entirely likely that Trump’s conspiracy theories will get at least some of the same credulous coverage they got last time around.

The post-impeachment polling on this issue suggests that segments of the public are vulnerable on this issue. A mid-February Politico-Morning Consult poll found that 30 percent of independent voters were “less likely” to support Biden as a result of the controversy, while only 5 percent were “more likely” (41 percent said it made no difference). Twelve percent of Democrats said that it made them less likely to support the former Vice President as well.

Make no mistake: Trump, Republicans, and the Fox News-Rush Limbaugh cinematic universe are salivating at the prospect of talking about Hunter Biden, Ukraine, and Washington corruption for the next few months.

In between the end of Trump’s impeachment in early February and the South Carolina primary at the end of the month, we heard virtually nothing about Ukraine or Burisma. Yet on Monday, when it became clear that Biden’s surge was real, Sen. Johnson announced that he wants to subpoena Hunter Biden to testify about Burisma. As with his Wednesday comments about a report on Burisma, the timing couldn’t be more transparent.

You can’t expect impartiality from the executive branch either, to put it mildly.

Trump has already attempted to pressure Ukraine to open an investigation into Biden, even going so far as to potentially violate the law by holding up military aid to Kyiv. In the midst of this scandal, he openly called on China to investigate Hunter Biden’s business dealings in that country. He has an attorney general in Bill Barr who is demonstrably willing to bend the Justice Department to his will.

There are all sorts of different ways — policy levers foreign and domestic, an entire media infrastructure beholden to him — that Trump can go in an effort to make Biden look shady. And it seems, judging from some of his recent behavior, that the impeachment acquittal has convinced Trump that he’s untouchable.

The fact that Joe Biden himself didn’t do anything wrong is, unfortunately for him, somewhat immaterial. What matters is creating a cloud of scandal and corruption around the Democratic nominee. That was enough to do serious damage to Clinton; it could potentially do the same to Biden.

To be sure, it’s not foreordained that such a faux scandal would sink his campaign. Clinton did have more baggage coming into the 2016 election than Biden does heading into 2020. Trump’s baseless accusations might be less effective the second time around.

It’s also fair to note that if Sanders were the nominee, the Republicans would also find something to tar him with. His wife Jane has legal problems surrounding her time as president of a small Vermont college, for example, that Republican-aligned media has already started probing.

But Jane Sanders was not a key figure in a national debate over impeachment, and so attacks on her may not resonate as much. Besides, Biden is explicitly running as the person who’ll restore dignity to the White House in a way Sanders isn’t — a message that is more vulnerable to the relentless drumbeat of Hunter Biden “bombshells” from Fox News and partisan Republican investigators on the Hill and credulous coverage from the mainstream press.

Choosing Biden means betting that this won’t play out as poorly as it could — on a particular theory, in other words, of how the public will react to the inevitable Republican deluge of Hunter Biden smears. It’s not obvious that we should have more certainty about the Biden theory of electorate than the Sanders one — that voters will be deaf to Republican efforts to paint him as an authoritarian communist.

If they do settle on Biden, Democrats may well go into the November election much like they did in the 2016 election: with an increasingly unpopular Democratic candidate hobbled by accusations of corruption. The worry is that Democrats haven’t thought through this possibility as they make their decision in the primary — that their safe choice to run against Trump might not be as safe as they think he is.