Obama ad highlights independence

Barack Obama quickly responded this afternoon to Hillary Clinton's TV ad suggesting that she alone is tough enough to be president with an ad of his own arguing that he is more independent, has better judgment, and doesn't stoke fear.

"Who has what it takes to really bring change?" the announcer asks in the spot to air in Pennsylvania before Tuesday's primary. "To finally take on the special interests -- not take their money. Who made the right judgment about opposing the war and had the courage and character to speak honestly about it. And who in times of challenge will unite us - not use fear and calculation to divide us."

The ad ends by showing Obama giving one of his uplifting speeches. "We are one people. All of us pledging allegiance to the stars and stripes. All of us defending the United States of America," he says.