Senate Democrats returned on Monday after a long recess — and after the Justice Department found additional classified documents during a 13-hour search of Biden’s home in Wilmington, Del. The discovery of those documents, on top of classified materials found in November and December, has created a political headache after Democrats sought to hammer Trump for his handling of classified material.

The issue is also an unwelcome one for the party, as Democrats have sought to focus their attention on House Republicans’ chaotic start to the 118th Congress. What’s more, classified documents could animate the presidential campaign if Biden runs for a second term, as is expected.

“I hope they found them all,” Durbin said of the Biden administration’s hunt for more documents. As for the president, Durbin observed: “He has done well by cooperating every step of the way, unlike Trump, but he still has documents that I don’t understand why he’d have in his personal possession.”

When asked about the criticism from Democratic senators, White House spokesperson Ian Sams told reporters on Monday that Durbin had also emphasized that Biden was “handling this in the right way” and that “full cooperation is the right way that this should be handled.”

It’s also not a full-on rebellion. Democrats reject comparisons with Trump, who is under investigation for retaining highly sensitive national security documents at his Mar-a-Lago estate in Florida — and for allegedly obstructing investigators seeking to recover them. They argue that unlike Trump, Biden’s legal team turned over the documents upon their discovery and invited the Justice Department to search for more.

Senate Minority Whip John Thune (R-S.D.), however, said the discovery of the Biden documents “neutralizes the issue” politically.

“They’re trying to attack former President Trump. Biden was chair of the Foreign Relations Committee” when he was in the Senate, Thune said. “He should have known better. And they were trying to claim the high ground on this issue when the shoe was on the other foot. And I think it’s a very tough issue for them to have to navigate right now.”

Other Democratic senators defended Biden and are still highlighting a contrast with Trump. Retiring Sen. Debbie Stabenow of Michigan, the No. 3 Democratic leader, said Biden was “doing exactly the right thing,” adding: “I wish former President Trump had done that rather than arguing they were his papers.”

Still, not every Democrat wants to make the comparison with Trump. Kelly suggested that the distinction between Biden and Trump’s situations was “up to somebody who actually does an investigation.”

And he said it was an issue he was paying close attention to: “I spent 25 years in the United States Navy. I take this stuff very seriously, personally. … Folks, you know, shouldn’t be taking classified documents out of federal government buildings and out of classified settings.”

Many Democrats are not eager to opine on the Biden documents, and several said they would withhold judgment and wait until the results of special counsel Robert Hur’s investigation. (The Justice Department previously appointed a different special counsel to investigate Trump’s handling of classified documents.)

“You have to get the answers to the questions before you reach a judgment,” said Sen. Tim Kaine (D-Va.), who is running for reelection in 2024. “If it’s a handful of documents and they’re not very serious, and maybe they were once classified but they’re not anymore, and there’s a good explanation for why he had them — but you don’t know the answer to those questions.”

Meanwhile, Sen. Tammy Baldwin (D-Wis.), who is also up for reelection in a purple state, said Biden was “cooperating thoroughly and proactively.”

Some Democratic committee chairs, while declining to criticize Biden, have said they want to look at the handling of classified documents broadly. Senate Intelligence Committee Chair Mark Warner (D-Va.) earlier this month called for a briefing related to both the Biden and Trump documents. He told reporters on Monday that he hoped for an update soon.

Sen. Gary Peters (D-Mich.), chair of the Homeland Security and Governmental Affairs Committee, said his panel was also looking broadly at the retention of records. Peters, who also runs Democrats’ campaign arm, said he wanted to deal with the issue “for presidencies in general. And we’re going to try to do that in a nonpoliticized way.”

Jordain Carney and Kyle Cheney contributed to this report.