In the beginning, in the real-life White House, he was Rahmbo. Then, in a television show, he was the fictional Josh. Now he is to be Leo.

Rahm Emanuel, who will be Barack Obama’s chief of staff, is a flesh-and-blood legend in a political party where art imitates life only until life starts imitating art.

Mr Emanuel was the model for Josh Lyman, the brilliant, controversial deputy chief of staff in President Bartlet’s administration in the hit series The West Wing. This came about because Josh was created by Aaron Sorkin and played by Bradley Whitford, both of whom are clients of the powerful Hollywood agent Ari Emanuel, Rahm’s brother.

Mr Emanuel was unimpressed by The West Wing, claiming that he did not watch it. “Been there. Seen it. Done it,” was his pithy response. But the parallels between himself and Josh are fun to trace now that he is back in power.

Like Josh, he worked on his president’s first victorious campaign. After his win in 1992, Bill Clinton recalled: “My first impression was, ‘This guy is going to help us win’. And he did. I doubt we could have done it without him.” As President Clinton’s political director, Mr Emanuel’s style upset a lot of people and he made mistakes that led to his being demoted, apparently at the behest of Hillary Clinton. Chastened, he stayed on and worked his way back into favour.

Josh, too, lost some power and influence after making a mistake early on. He, too, recovered. But in his case the First Lady persuaded the President to bring him in from the cold.

The real aide and his fictional counterpart are both tough, fast-talking Jewish men. Mr Emanuel is more devout. Josh went to Harvard and Yale Law School, whereas Mr Emanuel went to a small college and Northwestern University in Chicago. Mr Emanuel, married with three children, is more successful at long-term relationships. It took Josh aeons to get it together with his assistant, Donna, although he suffered at the hands of meddling scriptwriters who wanted to keep the sexual tension crackling right until the end.

Mr Emanuel is more profane than Josh is allowed to be on prime-time television. It was reported that at the height of the Monica Lewinsky scandal, he told Tony Blair before a joint public appearance with Mr Clinton: “This is important. Don’t f*** it up.” He sent a dead fish to a pollster and attacked a dining table with a steak knife while spitting the names of Democrats he accused of being disloyal.

Both men can be funny. “I wake up some mornings hating me too,” Mr Emanuel once said. When he lost the middle finger of his right hand in an accident as a teenager he said: “Of all the fingers to lose! I had to learn to talk with my left hand.” But is it possible that after he left the White House and became a banker and then a Congressman, Mr Emanuel really did not watch The West Wing? There was a terrific plot line in the final series in which Josh leaves the White House to run the presidential campaign of a long-shot ethnic-minority candidate who triumphs and makes him his chief of staff.

In his second White House incarnation Mr Emanuel must be Leo McGarry, who was Bartlett’s chief of staff. Some have suggested that Mr Emanuel’s tough style — a former Clinton staffer once joked that “someone should open a special trauma ward in Washington for people who’ve worked for Rahm” — makes him an odd choice for a President-elect seeking to heal wounds. But a tough can-do operator is probably what the more cerebral Mr Obama needs.

“He’s a little bit larger than life,” Mr Obama once said of his pal. “We like them with a little bit of personality.”

It is not a job requirement to be likeable and respectful to all who seek access to the President. Donald Rumsfeld and Dick Cheney, who both occupied the chief of staff’s chair in Gerald Ford’s White House, do not lack abrasiveness. John Sununu, George Bush Sr’s chief of staff, was known as his “bad cop” with a reputation for astonishing rudeness.

Mr Emanuel dithered over accepting the job because he was on a trajectory that might have taken him to a top job in Congress and because he was worried about the effect on his young family. The work is onerous. The average time served is 2½ years. Andrew Card, George W. Bush’s first chief, was the second longest-serving at five years. He would rise at 4am and be in the office at 5am. He would not leave until after Mr Bush went to bed. Fortunately for him that was about 9.30pm.

The chief of staff must be the President’s gatekeeper, choosing who gets into the Oval Office and overseeing his schedule. He liaises with all other senior aides, shaping the presidency by selecting priorities for the Commander-in-Chief. His office is quite small, but it is just a few paces from the Oval Office and opens on to the reception area through which visitors pass on their way to the boss. He misses nothing.

Where could Mr Emanuel go to from here? Leo, after his stint as chief of staff, was elected vice-president. Unfortunately, the stress took its toll. Shortly before the polls closed on the West Coast he suffered a heart attack. It did not alter the result, but it did kill him.

What happens to a former Chief of Staff?

Dick Cheney
Chief of staff to Gerald Ford 1975-77. Served as Defence Secretary under George Bush Sr before becoming Vice-President

James Baker
Ronald Reagan’s chief of staff 1981-85. Became his Treasury Secretary, Secretary of State under George Bush Sr and Chief of Staff again

Mack McLarty
Served Bill Clinton 1993-94. Joined Henry Kissinger in Kissinger McLarty Associates, a consulting firm, but the two later parted company

John Podesta
Clinton’s fourth chief, from 1998-2001. Became President of the Centre for American Progress, a progressive think-tank. Now heading Barack Obama’s transition team

Andrew Card
George W. Bush’s right-hand man 2001-06. Serves on the board of Union Pacific Railroad

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