President-elect Joe Biden’s incoming administration is in danger of not having a single Cabinet official confirmed on Inauguration Day, upsetting a tradition going back to the Cold War of ensuring the president enters office with at least part of his national security team in place.

Delays in Congress, caused primarily by runoff elections in Georgia for Senate seats that Democrats flipped this week and the arcane procedures needed to get the new chamber up and running, have sparked deep concern among Biden’s top advisers. They are now mapping out contingency plans to install acting secretaries in most, if not all, Cabinet posts, in case Biden’s nominees are unable to secure Senate backing by Jan. 20, according to those familiar with discussions.

“The American people rightfully expect the Senate to confirm his crisis-tested, qualified, history-making cabinet nominees as quickly as possible,” Ned Price, the national security spokesman for the Biden transition team, said in a statement. “With so much at stake, we can’t afford to waste any time when it comes to leading the response to the deadly coronavirus crisis, putting Americans back to work, and protecting our national security.”

The Fix’s Eugene Scott analyzes some of President-elect Joe Biden’s Cabinet picks and why he is under ongoing pressure to make more diverse picks. (The Washington Post)

For decades, Senate Republicans and Democrats have shelved their political differences to ensure a seamless transition between administrations, especially in the departments responsible for safeguarding the country against foreign and domestic threats. At a time when the United States is reeling from a massive cyberespionage campaign of presumed Russian origin, Iran’s resumed uranium enrichment, the deadly pandemic and volatile domestic unrest, the need for continuous leadership is considered especially paramount.

To date, the Senate Republican committee chairs — who will remain in control until Jan. 20 — have scheduled only one confirmation hearing for a Biden nominee: that of Lloyd J. Austin III, the president-elect’s choice for defense secretary. That lags well behind the pace of previous transfers of power between administrations, and many Republicans increasingly believe it will be impossible to expedite things.

The scenario would set up an unprecedented moment in which every Cabinet post would have an acting secretary, with either the top career official in a given federal agency taking the helm or some temporary official appointed by Biden.

The Senate Armed Services Committee said Thursday that it would hold a confirmation hearing for Austin, a retired Army general, on Jan. 19. The panel also announced that it would hold a hearing next week — while the House and Senate are out of Washington — to prepare a waiver allowing Austin to serve as the civilian leader of the Defense Department, despite having been retired from active military service for less than the required seven years.

That schedule could allow the Senate to squeeze in Austin’s confirmation just in time for Biden’s inauguration. But the House must also approve Austin’s waiver for him to take office — and as of yet, that chamber has issued no similar plans for its consideration. The House Armed Services Committee, which has requested to meet with Austin, has not scheduled its hearing either.

Should lawmakers fail to remedy the impasse, Biden will become only the second newly inaugurated president in the past 45 years to not have his choice for secretary of defense in place on the first day, according to Senate records. George H.W. Bush, in 1989, is the only other president not to immediately get his Pentagon chief confirmed, as his initial nominee, John Tower, fell into a bitter confirmation fight that ended in defeat.

The problem is not limited to the Pentagon. In years past, the Senate has scrambled to furnish incoming presidents with some combination of their picks to lead the State Department, the Department of Homeland Security and the intelligence community — all of whom this year are in danger of being stuck in limbo when Biden takes office.

In the Senate Foreign Relations Committee, secretary of state nominee Antony Blinken’s confirmation stalled amid a partisan dispute over whether the candidate has furnished the panel with satisfactory answers to prehearing questionnaires. Blinken submitted his paperwork to the panel on Dec. 31, according to aides familiar with the process, and has yet to meet with the vast majority of the panel’s members — a situation that has given rise to partisan finger-pointing about who is to blame, and insinuations from Democrats that the GOP chairman, Sen. James E. Risch of Idaho, is intentionally drawing out the process.

On the Senate Homeland Security and Governmental Affairs Committee, there has been similarly little action on Alejandro Mayorkas, the nominee for secretary of homeland security. The process has been complicated to a transfer of power on the GOP side between outgoing Chairman Ron Johnson (Wis.) and ranking Republican Sen. Rob Portman (Ohio).

Despite the confusion, Senate Democrats have argued that the Republican leaders of those panels could make a gesture of good faith by scheduling committee hearings with the nominees. Now that the results of Georgia are known, it is possible that the incoming Democratic chairs could try to take matters into their own hands and call meetings to discuss the pending nominations, with or without the consent of the outgoing GOP chairs.

But until the panels are officially formed and blessed by the full Senate — which cannot happen until Georgia certifies that Raphael Warnock and Jon Ossoff won their elections and they are formally seated in Washington — no committee can report out any nomination to the floor for confirmation.

The Biden transition team has taken pains to ensure that if there are delays, they aren’t coming from its end. A senior Biden transition official said that all outstanding financial disclosures for key nominees will be transmitted to the relevant Senate committees by the end of the week.

Yet even in committees that have not hit political or organizational snags, the task of delivering Biden a full national security team has been selectively hampered by the transition team’s decision-making process.

Democratic and Republican aides on the Senate Intelligence Committee have expressed total confidence that they will find a way to confirm Avril D. Haines as director of national Intelligence by Inauguration Day. But Biden has yet to name a director for the Central Intelligence Agency, also traditionally considered a priority post.

On President Trump’s Inauguration Day in 2017, the Senate convened and confirmed Jim Mattis and John F. Kelly as secretaries of defense and homeland security, and took an initial procedural vote on Mike Pompeo’s nomination to be CIA director, easily confirming him three days later. Even that slight delay on Pompeo outraged Republicans who said it endangered national security, led by the late Sen. John McCain (R-Ariz.).

“Why the hell don’t we just go ahead and give the president his national security team when we need it more than any time in recent history?” McCain said Jan. 20 in a speech.

On Jan. 20, 2009, Democrats had cried foul when Republicans declined to confirm Hillary Clinton as secretary of state until the second day of President Barack Obama’s administration, despite confirming six other Cabinet nominees on Day One.

The 50-50 split in today’s Senate adds an extra layer of complication, as the Republican committee chairs will remain in control of the chamber’s panels until Jan. 20, when Vice President-elect Kamala D. Harris is formally sworn in and can break the tie to make Sen. Charles E. Schumer (D-N.Y.) the majority leader. The last time a 50-50 Senate hampered the confirmation of a new Cabinet — for George W. Bush in 2001 — the two Senate leaders, Republican Trent Lott and Democrat Thomas A. Daschle, hammered out a power-sharing agreement, allowing for early confirmation hearings and a smooth transition.

Aides in both parties acknowledged that the partisan discord of 2021 makes similar comity unlikely. But after Wednesday’s riot at the U.S. Capitol, there is increased pressure on Majority Leader Mitch McConnell (R-Ky.) to ensure as smooth a transition as possible — and that includes giving Biden his national security team.