From Washington post http://www.washingtonpost.com/wp-dyn/content/article/2008/06/03/AR2008060304268_pf.html
Almost from the beginning, Hillary Rodham Clinton's superior name
recognition and her sway with state party organizations convinced Barack
Obama's brain trust that a junior senator from Illinois was not going to be
able to challenge the Clinton political machine head-on.
The insurgent strategy the group devised instead was to virtually cede the
most important battlegrounds of the Democrat