White House Chief of Staff William M. Daley resigned from his post Monday, and President Obama announced Jacob Lew, the head of the Office of Management and Budget (OMB), was to replace him. As David Nakamura reported:

Last January, Obama tapped Daley to replace Rahm Emanuel with high expectations. Daley, a former banker who also served as commerce secretary in the Clinton administration, was expected to help the White House improve relations with Wall Street as it implemented a series of financial reforms in the recession’s wake.

But Daley never seemed comfortable in the job, drawing wide criticism for his handling of the bitter and protracted legislative battles between the White House and Congress during much of 2011 that helped drag down the president’s public approval ratings.

Daley struggled to develop relations with members of both houses of Congress, and after he relinquished day-to-day operations to senior adviser Pete Rouse in the fall, his role seemed significantly reduced.

In a brief appearance at the White House on Monday, Obama announced that Daley, 63, will be replaced by budget director Jacob J. Lew, effective at the end of the month. Daley will stay in the job through the president’s State of the Union address Jan. 24 to help ease the transition.

Traditionally, the role of a White House chief of staff has included managing daily operations of the staff, weighing in on domestic and foreign policy, and helping manage relationships between the White House and Capitol Hill, Wall Street and other outside groups.

Whereas the fiery Emanuel, who had been a congressman before joining the White House and left to run for mayor of Chicago, was intimately involved in most of Obama’s decisions on politics and policy, the cooler Daley was said to have taken a more CEO-like approach to the job. Congressional Democrats complained privately that Daley acted as if they were “wasting his time,” and Senate Majority Leader Harry M. Reid (D-Nev.) never embraced him.

While some had been cool on Daley in his role as White House Chief of Staff, some analysts see his departure as a sign of changes to come in the Obama agenda for 2012. As Chris Cillizza explained:

White House chief of staff Bill Daley’s abrupt decision to resign his office caught official Washington by surprise as it came just a year after he was named to the job.

Obama praised Daley in announcing his departure, casting him as someone willing to make tough decision on the fly. “Chicago is only a phone call away,” Obama said, adding that he would continue to seek Daley’s counsel in the coming months. (And Daley is expected to serve as a co-chairman of Obama’s re-election campaign.)

Daley’s departure raises a bigger question, however. Brought in to rebuild the White House’s relationship with the business community and Congress, Daley leaves the job as Obama seems to have found his stride by explicitly running against Congress and, to a lesser extent, the business community.

“What he learned was that business refused to make nice regardless of what he did,” said one former White House aide of Daley. “Wall Street was just never going to be there.”

Another former aide said only that Daley was “not the right fit for the job”, adding: “ [Incoming White House chief of staff Jack] Lew is well-liked and a perfect fit for no-drama Obama team in a key year.” The aide would not expand on that critique.

Some analysts see Jack Lew’s move to the White House as a strategic decision to reduce friction within the administration and in its relations with Congress. As Ezra Klein reported :

Imagine you took Rahm Emanuel and split him into two people. One of the new Rahms was the pure political animal, the wartime consigliere, the tireless fundraiser, the maniac who jams steak knives into the table while calling out the names of his enemies. You took that guy and put him in charge of your campaign.

The other new Rahm was the policy wonk, the congressman who was Sen. Ron Wyden's first House cosponsor for his comprehensive tax plan, the policymaker who partnered with superwonk Bruce Reed to coauthor 'The Plan: Big Ideas for Change in America.' You took this Rahm and put him in charge of the White House.

What's the first thing your two Rahms would do? Well, given their personalities, and their different focuses, they would fight.

Monday's chief of staff shake-up brings the Obama administration pretty close to the two-Rahms scenario. Jim Messina, who served as Rahm's deputy chief of staff in the White House, is running the campaign. Messina is the political animal. He's the fixer. “You’d be in a meeting, and Rahm would bark out that something needed to be done," a former senior administration official told Politico. "Jim would disappear from Rahm’s office, pop through the door a few minutes later and say, ‘Got it!’ or ‘Got him!’”

And as of yesterday, Jack Lew, the mild-mannered budget wonk, is running the White House. I would include a funny story about Lew but there are, to my knowledge, no funny stories about Lew in the public record. It's possible something funny once happened involving Lew in private, but if so, the knowledge has long been lost. He does have a famously odd signature, but that's as close as we're going to get to a good anecdote. Lew is a guy who likes numbers and a guy who gets along with people. "Everybody likes Jack," said one former senior administration official. Even House Republicans.

That puts two very different guys, with very different political styles, and very different job descriptions, in charge of the two halves of Obamaland. And so the question is, what happens when they clash? What happens when the political side wants something that the policy side doesn't?

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