WASHINGTON — A blunder by House Democrats has revealed that Sidney Blumenthal, a longtime confidant of Hillary Clinton, gets paid around $200,000 a year for his part-time work promoting Clinton’s run for president.

Democrats on the House Benghazi Committee released a redacted deposition with Blumenthal on Monday as part of their 340-page report that absolved Clinton of wrongdoing in the 2012 attacks in Benghazi, Libya.

But the blacked-out exchanges were easily lifted by using a digital cut-and-paste function.

The transcript revealed that Blumenthal faced questions about his salary working for David Brock, a Clinton attack dog who established nonprofits designed to bat down right-wing attacks.

“What is your salary or your contract with Media Matters?” a questioner asked. “How much money are you earning from them?

“I’d say it’s about $200,000 a year,” Blumenthal replied.

Blumenthal said Brock hired him in 2012 and pays him for his work advising Brock-affiliated organizations, including Media Matters, Correct The Record and American Bridge.

Blumenthal spent nine hours answering closed-door questions before the House Benghazi Committee on June 16, 2015.

Republicans argued the grilling was necessary because Blumenthal routinely passed along detailed intelligence memos about Libya to Clinton.

Democrats charged Republicans were just trolling for information that could be used to hurt Clinton politically.