** FILE ** Former President Bill Clinton and President Obama wave to the crowd during a campaign event at the Waldorf Astoria on Monday, June 4, 2012, in New York. (AP Photo/Carolyn Kaster)

Photo by: Carolyn Kaster

** FILE ** Former President Bill Clinton and President Obama wave to the crowd during a campaign event at the Waldorf Astoria on Monday, June 4, 2012, in New York. (AP Photo/Carolyn Kaster)