Washington (CNN) White House aides have been told to decide before the end of January whether they intend to leave the administration or stay through the November midterm elections, an official said, a deadline intended to help bring a sense of order to an anticipated staffing exodus.

In recent months, top advisers on foreign and domestic policy have announced their departures. Additional aides are expected to make their exit in the coming weeks. Chief of staff John Kelly has embarked upon an effort to fill the ranks by the end of January. But the absence of willing and qualified replacements, paired with a lengthy hiring process, make it unlikely he'll reach that goal.

Kelly has been trying to take the reins of staffing in the West Wing since his elevation last summer. But the task has taken on heightened urgency.

"Kelly is eating bullets every day by himself and doesn't have a lot of help," said one person familiar with the personnel situation. "He needs reinforcements."

The White House rejected the idea of a deadline for staff to announce they're leaving or staying.

"There has been no directive on staff departures and any suggestion otherwise is ridiculous fake news," White House press secretary Sarah Sanders said.

'Doesn't it feel like a decade?'

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While a revolving door is common in any administration, people who work inside the White House with previous West Wing experience say the exhaustion is magnified remarkably under Trump. The unpredictability and chaos, along with a fear of costly legal fees in the wake of the Russia investigation, have added to the fatigue.

"It's been a year, but doesn't it feel like a decade?" a senior administration official said, speaking on condition of anonymity to discuss the sensitive nature of the personnel shifts.

Several of Trump's top advisers are still weighing whether to leave the administration at the one-year mark. Others appear likely to depart in the coming weeks.

Two of the most senior officials who are on the potential departure list are Don McGahn, the White House counsel, and HR McMaster, the national security adviser. The President, like with many of his advisers, has aired frustrations openly with both men. But it's far from certain whether either official will leave.

McGahn, who is a potential witness in special counsel Robert Mueller's investigation, has compelling legal reasons to stay at the White House, a person familiar with the matter said, despite the President's level of satisfaction.

McMaster, an active duty three-star Army general, served as a commandeering influence in the West Wing. But he has clashed with Trump over policy in Afghanistan and Iran.

Photos: Donald Trump's rise President-elect Donald Trump has been in the spotlight for years. From developing real estate and producing and starring in TV shows, he became a celebrity long before winning the White House. Hide Caption 1 of 37 Photos: Donald Trump's rise Trump at age 4. He was born in 1946 to Fred and Mary Trump in New York City. His father was a real estate developer. Hide Caption 2 of 37 Photos: Donald Trump's rise Trump, left, in a family photo. He was the second-youngest of five children. Hide Caption 3 of 37 Photos: Donald Trump's rise Trump, center, stands at attention during his senior year at the New York Military Academy in 1964. Hide Caption 4 of 37 Photos: Donald Trump's rise Trump, center, wears a baseball uniform at the New York Military Academy in 1964. After he graduated from the boarding school, he went to college. He started at Fordham University before transferring and later graduating from the Wharton School, the University of Pennsylvania's business school. Hide Caption 5 of 37 Photos: Donald Trump's rise Trump stands with Alfred Eisenpreis, New York's economic development administrator, in 1976 while they look at a sketch of a new 1,400-room renovation project of the Commodore Hotel. After graduating college in 1968, Trump worked with his father on developments in Queens and Brooklyn before purchasing or building multiple properties in New York and Atlantic City, New Jersey. Those properties included Trump Tower in New York and Trump Plaza and multiple casinos in Atlantic City. Hide Caption 6 of 37 Photos: Donald Trump's rise Trump attends an event to mark the start of construction of the New York Convention Center in 1979. Hide Caption 7 of 37 Photos: Donald Trump's rise Trump wears a hard hat at the Trump Tower construction site in New York in 1980. Hide Caption 8 of 37 Photos: Donald Trump's rise Trump was married to Ivana Zelnicek Trump from 1977 to 1990, when they divorced. They had three children together: Donald Jr., Ivanka and Eric. Hide Caption 9 of 37 Photos: Donald Trump's rise The Trump family, circa 1986. Hide Caption 10 of 37 Photos: Donald Trump's rise Trump uses his personal helicopter to get around New York in 1987. Hide Caption 11 of 37 Photos: Donald Trump's rise Trump stands in the atrium of the Trump Tower. Hide Caption 12 of 37 Photos: Donald Trump's rise Trump attends the opening of his new Atlantic City casino, the Taj Mahal, in 1989. Hide Caption 13 of 37 Photos: Donald Trump's rise Trump signs his second book, "Trump: Surviving at the Top," in 1990. Trump has published at least 16 other books, including "The Art of the Deal" and "The America We Deserve." Hide Caption 14 of 37 Photos: Donald Trump's rise Trump and singer Michael Jackson pose for a photo before traveling to visit Ryan White, a young child with AIDS, in 1990. Hide Caption 15 of 37 Photos: Donald Trump's rise Trump dips his second wife, Marla Maples, after the couple married in a private ceremony in New York in December 1993. The couple divorced in 1999 and had one daughter together, Tiffany. Hide Caption 16 of 37 Photos: Donald Trump's rise Trump putts a golf ball in his New York office in 1998. Hide Caption 17 of 37 Photos: Donald Trump's rise An advertisement for the television show "The Apprentice" hangs at Trump Tower in 2004. The show launched in January of that year. In January 2008, the show returned as "Celebrity Apprentice." Hide Caption 18 of 37 Photos: Donald Trump's rise A 12-inch talking Trump doll is on display at a toy store in New York in September 2004. Hide Caption 19 of 37 Photos: Donald Trump's rise Trump attends a news conference in 2005 that announced the establishment of Trump University. From 2005 until it closed in 2010, Trump University had about 10,000 people sign up for a program that promised success in real estate. Three separate lawsuits -- two class-action suits filed in California and one filed by New York's attorney general -- argued that the program was mired in fraud and deception. Trump's camp rejected the suits' claims as "baseless." And Trump has charged that the New York case against him is politically motivated. Hide Caption 20 of 37 Photos: Donald Trump's rise Trump attends the U.S. Open tennis tournament with his third wife, Melania Knauss-Trump, and their son, Barron, in 2006. Trump and Knauss married in 2005. Hide Caption 21 of 37 Photos: Donald Trump's rise Trump wrestles with "Stone Cold" Steve Austin at WrestleMania in 2007. Trump has close ties with the WWE and its CEO, Vince McMahon. Hide Caption 22 of 37 Photos: Donald Trump's rise For "The Apprentice," Trump was honored with a star on the Hollywood Walk of Fame in January 2007. Hide Caption 23 of 37 Photos: Donald Trump's rise Trump appears on the set of "The Celebrity Apprentice" with two of his children -- Donald Jr. and Ivanka -- in 2009. Hide Caption 24 of 37 Photos: Donald Trump's rise Trump poses with Miss Universe contestants in 2011. Trump had been executive producer of the Miss Universe, Miss USA and Miss Teen USA pageants since 1996. Hide Caption 25 of 37 Photos: Donald Trump's rise In 2012, Trump announces his endorsement of Republican presidential candidate Mitt Romney. Hide Caption 26 of 37 Photos: Donald Trump's rise Trump speaks in Sarasota, Florida, after accepting the Statesman of the Year Award at the Sarasota GOP dinner in August 2012. It was shortly before the Republican National Convention in nearby Tampa. Hide Caption 27 of 37 Photos: Donald Trump's rise Trump appears on stage with singer Nick Jonas and television personality Giuliana Rancic during the 2013 Miss USA pageant. Hide Caption 28 of 37 Photos: Donald Trump's rise In June 2015, during a speech from Trump Tower, Trump announced that he was running for President. He said he would give up "The Apprentice" to run. Hide Caption 29 of 37 Photos: Donald Trump's rise Trump -- flanked by U.S. Sens. Marco Rubio, left, and Ted Cruz -- speaks during a CNN debate in Miami on March 10. Trump dominated the GOP primaries and emerged as the presumptive nominee in May. Hide Caption 30 of 37 Photos: Donald Trump's rise The Trump family poses for a photo in New York in April. Hide Caption 31 of 37 Photos: Donald Trump's rise Trump speaks during a campaign event in Evansville, Indiana, on April 28. After Trump won the Indiana primary, his last two competitors dropped out of the GOP race. Hide Caption 32 of 37 Photos: Donald Trump's rise Trump delivers a speech at the Republican National Convention in July, accepting the party's nomination for President. "I have had a truly great life in business," he said. "But now, my sole and exclusive mission is to go to work for our country -- to go to work for you. It's time to deliver a victory for the American people." Hide Caption 33 of 37 Photos: Donald Trump's rise Trump faces Democratic nominee Hillary Clinton in the first presidential debate, which took place in Hempstead, New York, in September. Hide Caption 34 of 37 Photos: Donald Trump's rise Trump apologizes in a video, posted to his Twitter account in October, for vulgar and sexually aggressive remarks he made a decade ago regarding women. "I said it, I was wrong and I apologize," Trump said, referring to lewd comments he made during a previously unaired taping of "Access Hollywood." Multiple Republican leaders rescinded their endorsements of Trump after the footage was released. Hide Caption 35 of 37 Photos: Donald Trump's rise Trump walks on stage with his family after he was declared the election winner on November 9. "Ours was not a campaign, but rather, an incredible and great movement," he told his supporters in New York. Hide Caption 36 of 37 Photos: Donald Trump's rise Trump is joined by his family as he is sworn in as President on January 20. Hide Caption 37 of 37

Departing aides would join Dina Powell, the deputy national security adviser who announced her departure last year. An alum of the Bush administration, Powell was one of the only top-level aides with experience working in a White House. She's expected to remain a participant in senior adviser Jared Kushner's Middle East efforts, including joining Vice President Mike Pence on a trip to the region next week.

Other staffers who have departed, or who are expected to: deputy chief of staff Rick Dearborn, who is joining the private sector; Jeremy Katz, Cohn's deputy at the National Economic Council; Sean Cairncross, a senior adviser who Trump nominated to head the Millennium Challenge Corporation; and Omarosa Manigault-Newman, who was dismissed from her job as communications director at the Office of Public Liaison.

Gary Cohn, the National Economic Council chairman whose departure has been a constant subject of speculation since August, is still weighing whether to remain in his post, and for how long, people who have spoken with him say. He has committed internally to helping shepherd through an infrastructure plan, though it's not clear for how long. He declared on Saturday he was "happy" in his job when asked by Trump in front of reporters at Camp David.

Potentially in Trump's sights to replace Cohn, should he leave: Larry Kudlow, the conservative commentator, who speaks regularly with Trump and advised the White House on their tax reform efforts.

Empty benches

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Grueling hours, cramped offices and political warfare take sizable tolls on aides' personal and family lives. That reality has been exacerbated during Trump's first year in office, which was marked by chaos, internal backbiting and the constant specter of special counsel Robert Mueller's Russia probe.

Unlike previous presidents, however, Trump has alienated large swaths of Republicans who might otherwise leap at the opportunity to work at the White House. Some of Trump's allies, along with establishment Republicans, have voiced worry that a second wave of operatives and policy staffers does not appear to be waiting on the bench as aides announce their departures.

"There are still a lot of people who have said that they are unwilling to work in the White House and there are a lot of people that the White House is unwilling to have come in," said longtime Republican operative Doug Heye.

Trump's current team consists of "all qualified people who are trying to do the best for their country," Heye added, but it may be hard for the White House to find a stable of loyal people waiting in the wings to take over for them.

A wide array of GOP hands declined to join the administration when Trump was elected, either because they had denounced Trump as a candidate and weren't welcome in the West Wing or because they privately believed associating themselves with him would damage their careers.

A year later, those concerns have not abated. Trump is still adamant that the Republicans who criticized him the loudest not be awarded with jobs in his West Wing. And political careerists' concerns about the wisdom of joining the administration haven't been assuaged by a chaotic year, which is culminating with a debate over the President's mental fitness.

Another factor giving potential hires pause is the ongoing Russia investigation, which has led to four indictments and could soon include an interview with Trump. Some of those who might otherwise work for Trump view a White House job as a potential "ticket to the grand jury," one person familiar with the staffing challenges said.

Gaping political hole

The most gaping hole, according to multiple Trump allies inside and outside the White House, is that of a chief strategist who can channel Trump's populist appeal while translating it into policy and political wins. Since the departure of Steve Bannon over the summer, that position has remained vacant, leading to grumbling from some of Trump's allies at the state of his political operation.

Former campaign aides Corey Lewandowski, Jason Miller, David Urban and David Bossie have all been raised as possible candidates to fill the job. But whether they will pass muster from Kelly -- who has scant political experience -- or whether going inside the White House at this point is even feasible for them personally and professionally remains an open question.

Johnny DeStefano, who has gained Trump's trust over the past year, was assigned this month to oversee the White House's beleaguered Office of Political Affairs, currently under fire after electoral losses in Alabama, Virginia and New Jersey. The unit's current head Bill Stepien is expected to remain in place for now, but is still viewed skeptically by some of Trump's outside allies.

DeStefano will also continue to oversee the Office of Presidential Personnel, as well as taking responsibility for the Office of Public Liaison and the Office of Intergovernmental Affairs, people familiar with the plans said.

The vast portfolio represents a massive undertaking -- too massive, worry some officials, who have expressed concerns that DeStefano is being set up to fail. Mike Rubino, a Trump campaign aide who joined Lewandowski's lobbying firm, is considered a potential addition to help share some of DeStefano's burden, a person familiar with the deliberations said.

Allies also worry Trump lacks a senior-level aide with whom he enjoys a longtime relationship, in the mold of George W. Bush aide Karen Hughes or Barack Obama adviser Valerie Jarrett. The closest example is Kellyanne Conway, who became close to Trump on the campaign trail but has not been a longtime confidante. Keith Schiller, Trump's former security chief who joined him at the White House as an aide-de-camp, departed the administration in September and wasn't replaced.