Barack's Rock.(Barack Obama's valued adviser, Valerie Jarrett)

Byline: Photographed by Jonathan Becker

Senator Obama has one secret weapon in his wife, Michelle. The other is his chief confidante and valued adviser, Chicago businesswoman Valerie Jarrett. Just who is this hidden tower of strength? asks Jonathan Van Meter.

One day in the summer of 1991, when Valerie Jarrett was Chicago mayor Richard Daley's deputy chief of staff, the woman who worked in the office next door to Jarrett handed her the resume of one Michelle LaVaughn Robinson. Robinson was a young lawyer at Sidley Austin, the fifth-largest law firm in the world, doing marketing and intellectual-property work in their headquarters nearby. The resume highlighted the fact that the 27-year-old had grown up on the South Side of Chicago, had gone to Princeton and then to Harvard Law; what it did not point out was that her father, a city water-pump operator and Democratic precinct captain, had died of multiple sclerosis the year before, a shocking blow that led to a change of heart in the young lawyer about her choices in life. On the cover letter, someone at City Hall had written something like THIS WOMAN IS NO LONGER INTERESTED IN BEING AT HER LAW FIRM. SHE WANTS TO BE IN GOVERNMENT AND GIVE BACK. Susan Sher, the woman who worked in the office next to Jarrett, said, "She is made for you. This is exactly what you did." Jarrett immediately picked up the phone and called the young lawyer in for an interview.

"I was just unbelievably bowled over by how impressive she was," says Jarrett one August afternoon in her sunny, CEO-size, flower-filled office. She works for Habitat Company, one of Chicago's largest real estate management-and-development firms, where she has been since 1995 after leaving her final post at City Hall, as commissioner of planning and development. "Michelle was so mature beyond her years, so thoughtful and perceptive. She really prodded me about what the job would be like because she had lots of choices. I offered it to her on the spot, which was totally inappropriate because I should have talked to the mayor first. But I just knew she was really special."

The next step in this story is now the stuff of legend. Before Michelle Robinson would agree to take the job, she asked Jarrett to have dinner with her fiance, Barack Obama, who spent the two hours of their first meeting essentially interviewing his future wife's future boss (and, as things turned out, the couple's future best friend and Barack's future consigliere, and perhaps the future White House chief of . . . but that is getting ahead of ourselves a bit). When I ask Jarrett, who is a calm, compact woman with a twinkle in her eye and an easy laugh, if the story about the dinner back in July of '91 is all true, and I use the word grilling to describe the evening, she says, "It's all completely true--except I wouldn't say it was a grilling. Because Barack never grills. That's part of what is so effective about him: He puts you completely at ease, and the next thing you know he's asking more and more probing questions and gets you to open up and reflect a little bit. That night we talked about his childhood compared to my childhood and realized we both had rather . . . unusual childhoods."

Much has been made of Barack Obama's unusual childhood: It has been the subject of a book, the "story" of much of his campaign, and lately a weapon that has been used against him by the McCain campaign--a risky strategy to paint him as not quite American enough; one, we recently learned from leaked E-mails, that Hillary Clinton considered and wisely rejected. Jarrett had a similarly unconventional youth, which has seemingly done nothing to stop her from working her way deep into the Chicago establishment: She is ubiquitous on its institutions' boards and committees. Looked at one way, her career could easily read as prosaic--a success story that only a mother could brag about: six years as a real estate attorney, eight years at City Hall, now running a real estate company.

But Valerie Jarrett's real clout comes less from her career than from her extraordinary connections and seemingly endless capacity for extracurriculars. As one observer put it, ...