Obama Responds to Clinton in New Pennsylvania Ad

[youtube=http://youtube.com/watch?v=5gD9XWqEobg&w=260] 30-second ad counters Clinton's spot invoking the terror card, asks the question, "Who has what it takes to really bring change?" Indirectly cites claims of Clinton's ties to special interests, Iraq War vote, says: "And who in times of challenge will unite us - not use fear and calculation to divide us." Watch it above. Read script here. Plus: Read Obama camp's response earlier in the day here. Comes after Clinton 30-second Pennsylvania ad uses imagery of Osama bin Laden, Pearl Harbor attack, Hurricane Katrina. Ad doesn't reference Obama directly, but closes with, "Who do you think has what it takes?" Watch it here and read script here.