The Democrats unveiled their list of speakers shortly before the opening gavel at 4 p.m. ET.
Also scheduled is Eva Longoria, who spoke at the 2012 Democratic National Convention. Sarah Silverman, a supporter of Bernie Sanders, will introduce Sen. Al Franken (D-Minn.).
First Lady Michelle Obama and Sen. Bernie Sanders are among the main speakers Monday, with Sen. Elizabeth Warren (D-Mass.) delivering the keynote address.
The theme for opening night is “United Together.”
Other celebrities expected to speak in Philadelphia later in the week include actors Lena Dunham, America Ferrera, Tony Goldwyn and athletes Jason Collins and Kareem Abdul-Jabbar.
Hillary Clinton is expected to receive the party nomination on Tuesday, and is scheduled to deliver her speech on Thursday.