JOHNSTON, Iowa - With her political life on the line, Hillary Rodham Clinton is adopting a sweet-and-sour approach to win over an increasingly skeptical Democratic electorate in Iowa. During a pair of appearances Friday, Clinton made a powerful, emotional appeal to women voters by talking about her mother's troubled childhood. Then she quickly toggled to an attack on Barack Obama and John Edwards, suggesting she is the only contender who can't be hurt by damaging secrets. Appearing on Iowa Public Television, Clinton said she had been "vetted" by two decades of political combat and that "there are no surprises" in...