A survey by the Associated Press on Monday evening said Ms Harris had received the endorsement of more than the 1,976 delegates needed to win the nomination in the first round of voting.
Delegates are people who are selected to represent their electoral area at the Democratic National Convention (DNC), the party’s key nominating event.
Such endorsements are non-binding, but if the total holds between now and when delegates cast their votes, scheduled to take place from 1-7 August, Ms Harris would formally clinch the party’s nomination.
