House Republicans unanimously voted last week to formalize their impeachment investigation into Joe Biden. But according to one Democratic House member, the whole investigation remains smoke and mirrors.

“I’ve talked to numerous Republicans who have publicly and quietly said, ‘there’s no there there.’ They can’t find anything,” Rep. Debbie Dingell (D-Mich.) said Sunday during an interview on NBC’s “Meet the Press.”

The vote to formalize the investigation into what role the president may have played in his son Hunter’s business began nearly a year ago, but has not yet produced evidence that would incriminate the president. Some Republicans voiced hesitation about backing the politically charged process because of the lack of evidence unearthed so far, but the entire caucus ultimately backed the move.

“There were a lot of arms broken,” Dingell said. “I’ve talked to those members whose arms are broken about even voting for this on the House floor. And I think it will be much harder to get the number they will require to have an impeachment if they don’t find something.”

Some Republicans in the Senate have also expressed doubt that anything uncovered amounts to impeachment-worthy wrongdoing by the president.

Sen. Chuck Grassley (R-Iowa) said last week that he had seen “no evidence” that Biden was inappropriately involved in Hunter Biden’s business dealings.

“If there were a smoking gun I think we’d be talking about it,” Sen. Lindsey Graham (R-S.C.) said Sunday during an interview on “Meet the Press.”