Reluctant Pol

MICHAEL BLOOMBERG / NEW YORK

GREGORY HEISLER FOR TIME

NEW YORK: Bloomberg at work in his cubicle in the bullpen he set up at city hall

From the moment you enter his office at New York's city hall, Mayor Michael Bloomberg, 63, wants visitors to know that he is not your average politician--or a politician at all. Bloomberg, you see, doesn't really have an office. Instead, he sits alongside much of his staff in the middle of what is known as the bullpen, a large, former public meeting room now packed with corporate cubicles like a Wall Street trading floor. "Walls are barriers, and my job is to remove them," says the billionaire businessman who made his fortune by building his namesake financial-data-and-media empire. "I wasn't hired...