As of the last update, 143,335 votes had been counted in the runoff, with turnout at 33.7%. If the same number of people vote in the runoff as did during the special primary, Smith would need to win the remaining ballots 97% / 3% to close the gap. If turnout were to somewhat improbably reach the same levels as the 2018 general election (despite the near total absence of in-person voting, considerably fewer provisional ballots, and the disappearance of door to door ballot collecting efforts in the face of the stay-at-home order), a feat which would necessitate there being an additional 133,000 ballots still in transit, Smith would catch up if she carried 57% of the remainder.
Ventura County will report the totals from the in-person votes and votes dropped off at its vote centers later this afternoon, and given the way the in-person ballot went in L.A. County, it is not inconceivable that Garcia's margin could continue to grow when the more solidly Republican county updates. The initial uncounted estimates will be due out Thursday, with Los Angeles County posting updates on Fridays and Tuesdays until it completes its count.
Riverside County posted a single update yesterday evening, with Assembly District 67, Republican Assemblywoman Melissa Melendez jumping out to a 20,130 vote lead over Democrat Elizabeth Romero. Turnout is currently at 34.43%, with Melendez leading Romero by 11.8%.