2. Nancy Pelosi
Speaker of the House
Last year's rank: 1
She cemented her reputation as the driving liberal force in Washington by getting the House to pass a climate-change bill and persuading the Obama administration not to scale back health care reform. But a Republican takeover of the House could prompt her exit on a sour note.
NEXT: Mary Schapiro
Last updated September 29 2010: 11:28 AM ET
