A recent fundraising letter from Sen. Hillary Rodham Clinton, who is seeking re-election this year in New York, does not mention the state, but it slips eight references to "America" or "Americans" into two pages. The letter points to a fact of life in the world of New York's junior senator, who many think may be a contender for the 2008 Democratic presidential nomination: The national stage is there, and she is making use of it. In recent weeks, the wife of former President Bill Clinton has begun a series of national policy addresses. The economy was the topic in...