The AP looks at Chelsea Clinton's work with her family's foundation:
"It just seems so fundamental to me. I'm able to marry the person I wanted to marry," Clinton said. "That's the fundamental human imperative. Those of us who have been lucky enough should expand these rights to others."
Clinton often tweets messages supportive of gay rights. Earlier this month, she called it "progress" when France's new gay marriage law came into force and urged her followers to help build "an equitable world for all" while marking International Day Against Homophobia.