Congress approved a waiver Thursday for retired Gen. Lloyd Austin to lead the Pentagon under President Biden, clearing an important procedural hurdle for the Senate to confirm him as the first Black defense secretary — a vote that was expected Friday morning.

Austin needed lawmakers to waive the rule requiring former uniformed military personnel to be seven years removed from active service before they can become the defense secretary. He retired as a four-star Army general in 2016.

The House approved the waiver first, with a vote of 326 to 78 — representing strong bipartisan support, despite the fact that several House Democrats and an official House Republican policy group had opposed the waiver. The Senate followed suit about an hour later, backing the waiver by a vote of 69 to 27.

Opponents in both parties had argued that it would endanger the tradition of civilian leadership at the Pentagon for a second recently retired general to hold the position so soon after Jim Mattis, a retired Marine general who served as President Donald Trump’s first defense secretary.

But Republican and Democratic leaders in both parties appealed to their members not to vote simply on principle, citing their confidence that Austin was the right man for the job.

House Armed Services Committee Chairman Adam Smith (D-Wash.), despite his initial uneasiness with the waiver, emerged as one of Austin’s strongest champions Thursday, appealing to his colleagues to back the waiver to make sure Austin takes office as soon as possible.

“He deserves this waiver, and our country deserves a fully confirmed secretary of defense as soon as we can get that done,” Smith said on the House floor just before the vote.

Sen. James M. Inhofe (R-Okla.), the outgoing Senate Armed Services Committee chairman, also praised Austin on Thursday, calling him “a strong, capable civilian leader for the Pentagon at this critical time.”

The Senate confirmed Avril Haines as the director of national intelligence late Wednesday, installing her as the first member of Biden’s Cabinet. And while it appears Austin will become defense secretary on Friday, political pitfalls remain before several other nominees can assume key national security posts in the new administration.

Republican and Democratic lawmakers struck a handshake agreement Thursday evening to expedite the confirmation of Antony Blinken, whom Biden has nominated to serve as secretary of state. That all but sets up his nomination for confirmation, though any one senator can block the expedited confirmation of a nominee, sending the process back to the committee of jurisdiction for slower consideration.

It will be next week at the earliest before the Senate votes on Biden’s nominees to lead the Justice Department, the CIA and the Department of Homeland Security.

Of those three, only Alejandro Mayorkas, the DHS nominee, has had a confirmation hearing, and partisan disputes over his tenure in the Obama administration and his dealings with the Clinton White House have slowed the process.