AGE: 64 OCCUPATION: President, Cook County Board of Commissioners

If Rahm gets bored with the mayor’s office, there may be no better successor than this formidable, unsentimental former alderman. She has reformed Cook County government by firing Todd Stroger’s cronies, rolling back a portion of his one-cent sales tax increase, and laying off a slew of workers—tough but necessary moves that have reformed an office once considered a patronage dispensary.

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Photograph: Jose M. Osorio/Chicago Tribune