It had been a little while since we’d heard much from Republicans about “Sleepy” Joe Biden and his son, Hunter. The former vice president had suffered a string of humiliating finishes to open up primary season, and with his campaign was on the ropes, Burisma no longer seemed like a priority for Republicans.

But as Biden came roaring back over the weekend with a decisive win in South Carolina, so, too, have attacks from the president and his allies. Republicans like Ron Johnson, largely quiet about the Ukrainian energy company linked with the younger Biden since Trump’s impeachment acquittal, are suddenly interested once again. And Donald Trump, whose puerile attacks on Democrats of late have mostly focused on “Mini” Mike Bloomberg and “Crazy” Bernie Sanders, is now targeting Biden as his candidacy once again becomes a viable threat against him.

Speaking at a rally in North Carolina Monday, Trump portrayed Biden as a senile Trojan horse candidate for the “super-left, radical crazies” who would actually run a new Democratic administration. “Sleepy Joe,” Trump said of his 77-year-old rival. “He doesn’t even know where he is or what he’s doing or what office he’s running for. Honestly, I don’t think he knows what office he’s running for.”

“They’re going to put him into a home, and other people are going to be running the country,” the president continued. “And they’re going to be super-left, radical crazies. And Joe’s going to be in a home and he’ll be watching television.” Trump—an untethered 73-year-old who spends much of his day watching cable news—is perhaps uniquely unqualified to level such an attack. After the rally, Trump, who has made thousands of false and misleading claims in office, tweeted a Fox News clip highlighting Biden’s gaffes. “WOW!” he wrote, “Sleepy Joe doesn’t know where he is, or what he’s doing.”

In his own graceless way, Trump is tapping into perhaps the biggest concern that even some Democrats have about the former vice president. Factions of the Democratic party may have their misgivings about his stubborn, occasionally out-of-touch centrism. Others may worry that his ground game and resources aren’t enough to match Sanders, Bloomberg, or Trump. But one punch that has repeatedly landed on Biden is that he’s lost a step. That may or may not be true, but critics have had a wealth of campaign trail gaffes and off-kilter debate performances to point to in support of their attacks.

But Biden has enjoyed something of a return to form in recent days, appearing reenergized and making a strong case for himself as the race’s leading moderate with the post-South Carolina endorsements of former primary rivals Pete Buttigieg, Amy Klobuchar, and Beto O’Rourke. Sanders remains the frontrunner, of course, and a dominant Super Tuesday tamp down Biden’s momentum. But if Biden turns in a strong performance Tuesday, when more than 1,300 delegates are up for grabs, he could pull closer to the Vermont progressive—and again become a looming threat to Trump. “This is a guy who doesn’t know what he’s doing,” Biden said of Trump in a Fox News interview over the weekend, adding that he was eager to get onto a debate stage with the president. “I want people to see me standing next to him and him standing next to me,” Biden said. “We will see who is sleepy.”

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