AGE: 58 OCCUPATION: President, Chicago Teachers Union

This Dartmouth grad and former science teacher may be her own worst enemy (was it really necessary to mock Secretary of Education Arne Duncan’s lisp?). But with contract negotiations on the horizon (the current teachers’ deal expires June 30), the union solidly behind her, and the power to strike in her hands, this first-term prez looms as a potential roadblock to Mayor Emanuel’s efforts to remake Chicago’s public schools.

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Photograph: E. Jason Wambsgans/Chicago Tribune