��If They Bring a Knife to the Fight, We Bring a Gun”

Obama talks tough at Philadelphia fundraiser with Gov. Rendell, Mayor Nutter. Read pool report.

Adds: "Because from what I understand folks in Philly like a good brawl. I’ve seen Eagles fans.”

Rendell, a former Clinton supporter, says he has donated the full $2,300 to Obama's campaign.

Obama: "We're going to make sure this doesn't bounce."

Response from McCain camp:

"Barack Obama’s call for 'new politics' is officially over.  In just 24 hours, Barack Obama attacked one of America’s pioneering women CEOs, rejected a series of joint bipartisan town halls, and said that if there’s a political knife fight, he’d bring a gun." Read full statement.