Exclusive: Clinton Vows to Push On

Hillary Clinton is under a lot of pressure these days, but in a Tuesday interview she seemed cheery, confident and unapologetic as she talked about her determination to fight on in the presidential race. Speaking by phone from Pennsylvania, she explained why she plans to continue her push for the Democratic nomination, even as some question her chances of winning. She expressed confidence that her party would pull together in time to beat Republican John McCain, as well as a belief that the remaining contests — and perhaps some surprising shifts in the delegates already elected — would make her...