A prominent Democratic Party pollster Thursday said the reason members of his party have lost major elections in recent years is because they have not "run with conviction." Stanley Greenberg, who currently heads his own research firm, previously conducted polling and offered advice to then-President Bill Clinton, then-Vice President Al Gore, British Prime Minister Tony Blair, and South African President Nelson Mandela. Greenberg conceded that the biggest current weakness among Democratic candidates is that they "do not know what they stand for, they don't know their policy direction, they don't know their underlying values, they don't know who they fight...