How was the recall election called by news organizations, with millions of ballots left to count?

Gov. Gavin Newsom is expected to remain in his position after news organizations projected him as the winner of the recall election soon after polls closed on Election Day. How could this projection be made, if millions of votes remain uncounted? As of Thursday night, the California Secretary of State's Office says an estimated 2,918,010 ballots are still "unprocessed." Elections officials across the state have until Oct. 15 to send their final ballot totals to the secretary of state.