White House Budget Director Jack Lew. (Charles Dharapak/AP)

For hundreds of federal budget analysts, the Monday after Thanksgiving is a day to step back, take a deep breath and prepare for a stressful holiday season, marked less by parties and gift-giving and more by complex political maneuvering and tricky math.

“Passback Day,” as the last Monday of November is known in budget circles, is when the White House and the Office of Management and Budget literally pass back drafts of proposed budgets for the next fiscal year to agencies and departments and begin a series of negotiations in hopes of completing a final budget proposal for President Obama by January.

In previous years, White House officials passed back budget drafts the day before Thanksgiving, with an expectation that agencies would file formal responses shortly after the holiday. But OMB Director Jacob J. Lew said recently that he decided to move passback to after Thanksgiving, deeming the previous schedule “cruel and unusual punishment” for agency bosses hoping to spend time with family.

“Quality of life isn’t so high during this period,” Lew joked at an October breakfast hosted by Politico, noting that as budget director, “you go home with about three hours of reading every night, you have about two or three hours of meetings every day, and then you have the rest of your job to do.”

Before Thanksgiving, Lew and his team of aides at OMB reviewed budget proposals for about 25 agencies, with each meeting lasting about two hours. During the meetings, aides and veterans of the process said, Lew heard from OMB budget officials, known as program associate directors, who review spending for various parts of the government and set proposed limits. The numbers are either approved or sent back for revisions.

During the meetings, “the role of the director is to ask questions and to allow other people to ask questions,” said Alice M. Rivlin, who served as OMB director during the Bill Clinton years, and recalled that the process “is just nonstop.”

Despite last week’s failure of the fiscal “supercommittee” to reach a deal on cutting federal spending and no clear sense of how Congress may proceed on the issue in the coming weeks, OMB officials said that passback is expected to begin this week as scheduled.

Barry Anderson, who served as an OMB budget official for decades, said, “It’s going to be really strange to pass back without knowing” what Congress might decide to do about spending. “OMB may pass back a set of numbers that are fundamentally different than what the law will be, if Congress doesn’t find $1.2 trillion worth of cuts,” he said.

Once an agency reviews its proposed budget, veterans of the process said, mid-level OMB officials meet with agency budget directors to address questions and concerns. Serious disagreements are often addressed by the OMB director, who can take lingering funding disputes directly to the president.

During the Clinton years, Anderson and Rivlin said, two or three Cabinet secretaries might meet with the president to make a final plea for more money.

But Lew said agencies shouldn’t expect such flexibility this year.

“It’s not like I have some secret pot of money,” he said last month, adding later, “we’re at the place now where just because something will get a lower funding level doesn’t mean that’s a bad thing to do.”

Even if big budget decisions are made before Christmas, career OMB staffers still face weeks of work sorting out minute spending details.

“Somehow the career guys stick around and their families adjust to that kind of a holiday lifestyle,” said Steve McMillin, who served as deputy OMB director during the final years of the George W. Bush administration. “It’s really extraordinary how it’s set up to make the holidays very painful for those involved in the process.”

After the budget season ends, however, staffers get a bit of revenge.

For the past three decades, usually after the president submits his budget to Congress, OMB staffers have performed skits for the director that poke fun at current political developments and the personalities of top administration officials.

Rivlin said staffers often joked during the Clinton years about how she enjoyed taking long hikes along the Billy Goat Trail near Great Falls. “There was a guy on the staff who bore a very strong resemblance to Warren Christopher, so he always got to play the secretary of state,” she said. “And some short woman usually played me.”

During George W. Bush’s administration, McMillin said, staffers liked to joke about the low profile of then-director Joshua B. Bolten. One year, they produced a series of “man on the street” video interviews with people who were asked to pick Bolten out of a series of photographs that included head shots of the director, then-U.N. Ambassador John Bolton and singer Michael Bolton.

Lew doesn’t seem to mind the jokes from his staff.

“Budgets aren’t just about numbers, they’re about priorities, they’re about beliefs,” he said last month. “OMB is well-served by having a career staff that is just focused constantly on how well things are working and what we could do better.”

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