President Barack Obama calls out to media as he walks across the South Lawn to the White House from Marine One, Thursday, March 22, 2012, in Washington, as he returns from Ohio. (AP Photo/Carolyn Kaster)

Photo by: Carolyn Kaster

President Barack Obama calls out to media as he walks across the South Lawn to the White House from Marine One, Thursday, March 22, 2012, in Washington, as he returns from Ohio. (AP Photo/Carolyn Kaster)