Pennsylvania Gov. Ed Rendell (second from right) and Philadelphia Mayor Michael Nutter (left) greet President Obama upon his arrival at Philadelphia International Airport on Tuesday, Sept. 14, 2010. (AP Photo/Pablo Martinez Monsivais)

Photo by: Pablo Martinez Monsivais

Pennsylvania Gov. Ed Rendell (second from right) and Philadelphia Mayor Michael Nutter (left) greet President Obama upon his arrival at Philadelphia International Airport on Tuesday, Sept. 14, 2010. (AP Photo/Pablo Martinez Monsivais)