Washington (CNN)Hillary Clinton accused four potential GOP presidential rivals by name of being "scared of letting citizens have their say" as she called Thursday for every American to automatically be registered to vote. Clinton told an audience at the historically black Texas Southern University that she supports the concept of signing every American up to vote as soon as they're eligible at age 18, unless they specifically opt out. She called for expanded access to polling places, keeping them open for at least 20 days and offering voting hours on evenings and weekends. For the first time in her campaign,...