In her three years as U.S. secretary of education, Margaret Spellings has been a celebrity contestant on "Jeopardy!," a guest on "The Daily Show With Jon Stewart," and an occasional subject of Washington's best-read gossip column. Above all, though, she's been the nation's leading spokeswoman for the No Child Left Behind Act (NCLB). With one year left on the job and Congress stalled over reauthorizing the 6-year-old federal education law, the task of promoting and defending it is tougher than ever. But Ms. Spellings plans to continue her plain-spoken pitch for the NCLB law, which is one of President Bush's biggest domestic-policy accomplishments and something he wants to be part of his legacy. This article profiles Secretary Spellings.