WASHINGTON (AP) - Warning: Jelly doughnuts may be hazardous to your child's health. That's what Democratic presidential candidate Joe Lieberman is telling America's parents as he seeks a federal investigation into the marketing practices of junk food companies. The Connecticut senator, who led the fight to put parental warnings on movie, video game and music advertising, wants the Federal Trade Commission to determine whether there is a connection between junk food advertising and the rise in obesity among youngsters.``We're talking about how the government can get back on the side of parents and families and support them in raising healthy...