The Democrats' acrimonious primary battle came back to haunt Hillary Clinton yesterday, a day before she sets off on her first solo campaign swing for Barack Obama, with John McCain using footage of her attacking the Democratic candidate in a new campaign ad. The ad, which was released on the internet, features a number of Democratic leaders - including Obama - offering praise for McCain. But only Clinton, who is the closing speaker, goes so far as to take a jab at Obama, in footage culled from one of her primary rallies. The ad surfaced a day before Clinton is...