Senator Harris was ranked “The Most Left” by nonpartisan GovTrack

CBS: "You're considered the most liberal United States senator." KAMALA: "I— somebody said that, and it was actually Mike Pence on the debate stage..." CBS: "Actually, nonpartisan GovTrack has rated you as the most liberal senator."

https://web.archive.org/web/20221127062248/https://www.govtrack.us/congress/members/kamala_harris/412678/report-card/2019