She had been a supporter of Hillary Clinton's Democratic Party candidacy for President of the United States, from as early as September 2014 when Gillard announced that she would "loudly barrack from the sidelines" should Clinton run. Having endorsed Clinton after she announced her candidacy in April 2015, Gillard appeared in a campaign video in October, wherein she advocated for the presidential candidate and her leadership surrounding women's issues. Gillard attended the first day of the Democratic National Convention in Philadelphia on 25 July 2016, alongside former US Secretary of State Madeleine Albright. The following day, Gillard published an open letter to Clinton in the "New York Times", urging voters to "shame sexism" levied against the Democratic presidential candidate.