"I must be really easy to make fun of," Clinton joked.
Seven-time Grammy winner will.i.am also supports the Initiative, which carried the theme "Mobilizing for Impact" for this year's gathering.
"People come together and talk about issues," said will.i.am.
One issue already on Americans' minds is the 2016 election. The music star offered his endorsements for the Democratic Party, saying, "I think Hillary Clinton should run for president and Chelsea in a few years, too."