CNN  — 

President-elect Joe Biden enters the month of December with a question still looming over one of the most critical decisions in his Cabinet: Who will he nominate to be Secretary of Defense?

Three candidates are in final contention to lead the Pentagon, people familiar with the matter told CNN, as Michele Flournoy, Jeh Johnson and Lloyd Austin are all still being considered. But Biden’s delay in naming a nominee is giving space and time for critics to air their complaints – and the corporate connections of all three candidates are giving progressive Democrats grounds to object.

The pick is an important one, as it represents Biden’s first commander in chief decision in the new “post-war” era President Donald Trump leaves behind.

As a result, the candidates for defense secretary are facing increased scrutiny over whether they have the political chops to cut defense spending, as some in Congress want, while still funding innovative future technology and prioritizing the challenges posed by Russia and China – all while maintaining military deterrence against Iran, North Korea, and ISIS.

Sen. Tammy Duckworth, an Illinois Democrat and decorated combat veteran, is no longer getting a serious look, people familiar with the matter said, given Biden’s reluctance to create any vacancies in the Senate.

Flournoy, a veteran Pentagon official, was once widely considered a lock for the position and is still very much in the mix, people familiar with the matter told CNN, but her exclusion from a flurry of barrier-breaking selections in Biden’s first wave of Cabinet picks underscored an increasing uncertainty surrounding her candidacy.

Some progressive groups have mobilized in recent days to oppose Flournoy’s nomination, though the delay may also be due to the complicated puzzle Biden is assembling as he tries to fulfill his promise of building a Cabinet that reflects the diversity of America – a potential factor in the President-elect’s delay in naming a CIA director as well.

Critics have raised concerns about Flournoy’s potential conflicts of interest, questioning how her support for former President Barack Obama’s troop surge in Afghanistan and the continued sale of arms to Saudi Arabia aligns with the business interests of Booz Allen Hamilton, a Pentagon contractor where she served on the board of directors.

They have also pointed to Flournoy’s role as co-founder of WestExec Advisers, whose primary business is helping US companies with global footprints navigate geopolitical risk, as a concern. Flounroy founded the consulting firm with Biden’s pick for secretary of state, Antony Blinken.

“In Flournoy’s case, the seeming alignment between the interests of her clientele and her stated policy positions – such as her desire to continue selling arms to Saudi Arabia as late as 2019, which is out of step with Biden and essentially all congressional Democrats, is especially worrisome,” David Segal, co-founder and executive director of the group Demand Progress, told CNN.

A spokesperson for Flournoy pushed back on that assertion, telling CNN, “Michele’s private sector experiences do not influence her policy views or work.” The spokesperson also noted that Flournoy “has no involvement in contracting or business development with any client, including the US government” as a member of Booz Allen’s board of directors.

A WestExec spokesperson told CNN that the firm undertakes “an intensive client vetting process to ensure that the companies with which we work and the nature of the work we do for them meet our strict ethical standards.”

Candidates face scrutiny over ties to defense contractors

While serving on the board of a defense contractor is considered a conflict and typically requires a cooling off period before anyone can be nominated as defense secretary, others in the position have had similar backgrounds.

Other candidates Biden is considering for the post also have ties to defense contractors.

Johnson is on the board of directors for defense giant Lockheed Martin Corp., while Austin is on the board of directors for another weapons contractor, Raytheon Technologies.

Johnson served as general counsel at the Pentagon, as well as secretary of Homeland Security.

Austin, a retired Army general who led Central Command during the Obama era, would need a congressional waiver to be confirmed for the civilian post because he retired from active-duty service only four years ago.

Johnson and Austin, who are African American, would be history making nominees as the first Black secretary of defense. So, too, would Flournoy, as the first woman to run the Pentagon.

Those factors, the criticism and the importance of the post create a fine-tuned political challenge for Biden involving Congress and allies – making their views on the nominee important to take into consideration.

Some Democrats on the Senate and House Armed Services Committee have voiced public support for Flournoy in recent days.

“Michele Flournoy has a deep understanding of the existing DOD bureaucracy and the future of our defense. That’s a rare combination. I would love to see her nominated for Secretary of Defense,” Rep. Seth Moulton, a Massachusetts Democrat who served in the Marines and is on the House Armed Services Committee, wrote in a tweet last week.

A Democratic Senate aide told CNN last week that senior members of the panel also believe Flournoy would be a good choice but said there has been little direct contact with the Biden transition and lawmakers remain mostly in the dark as to who the President-elect will ultimately nominate.

In a letter to Biden earlier this month that did not name Flournoy, but was widely viewed as pushback on her potential nomination, Democratic Reps. Mark Pocan of Wisconsin and Barbara Lee of California, two leading House progressives, requested “that the next Secretary of Defense have no prior employment history with a defense contractor.”

For her part, Flournoy sought to address some of those concerns in a recent call with progressive foreign policy groups, two sources – including one on the line for the discussion – told CNN.

“She is interested in understanding the views of progressive groups, and that’s why she has met with them. To hear, firsthand, their perspective. And to clarify any misperceptions that exist about her positions,” said another source familiar with the conversation and Flournoy’s view of the situation.

“I expect that if she is nominated that these conversations will continue,” the source added.

A source familiar with Flournoy’s thinking told CNN that her interest in serving on the board of private companies is, in part, to learn. “How can you hold industry accountable and conduct good oversight of acquisition if you don’t understand it?” they said.

Asked if Flournoy will reveal her clients if nominated for the defense secretary job, her spokesperson said: “As always, Ms. Flournoy will fully comply with the law and any disclosure requirements.”

The announcement about the Pentagon’s next leader is still expected soon – perhaps later this week or next – but the exact timing is contingent on a final decision that as of late Sunday evening had not been reached, people familiar with the matter said.

Biden weighs options for CIA director

The Defense Department opening is not happening in a vacuum.

Biden is also still searching for someone to lead the Central Intelligence Agency – and Johnson is also believed to be at least under consideration for that post, people familiar with the matter said.

Former CIA Acting Director Mike Morell also remains a contender, as CNN has previously reported, but his status as a frontrunner has been tested with a barrage of attacks from Senate Intelligence Committee Democrat Ron Wyden, who has accused him of being a “torture apologist.”

Since Wyden’s attacks, senior transition officials have spoken with other Democratic senators, including members of the Senate Intelligence Committee, to discuss possible candidates to lead CIA.

In addition to Morell, Sue Gordon, a former principal deputy Director of National Intelligence, is also a contender, people familiar with the matter told CNN, as is Vincent Stewart, a former leader of the Defense Intelligence Agency and Marine general. He, too, would require a congressional waiver to serve in the civilian post.

The Intelligence Committee is the first gauntlet on the path to confirmation and Gordon “would be very popular if nominated,” one of the aides told CNN, suggesting she may have an easier time being confirmed than Morell if he starts taking more fire from progressives.

“I would always serve my country,” Gordon told CNN on Monday. “If asked I would serve.”

Former senior Obama adviser Lisa Monaco and former CIA deputy director David Cohen are also in the running, multiple sources familiar with the discussions say.

Tom Donilon, a former national security adviser to Obama who had been among the top contenders to lead the CIA, is no longer under consideration for that post, CNN reported Sunday.

A transition official said the announcements for Pentagon and CIA would be made when Biden reaches his decisions, dismissing any suggestions of a delay. Nominations for both posts, in addition to others in the Cabinet, are expected in December.

CNN’s Alex Marquardt, Barbara Starr and MJ Lee contributed reporting