California had two statewide ballot measures on the ballot this month that relate to voter eligibility. Proposition 17 passed. It lets individuals on parole register to vote, and passed with 59%. Proposition 18 failed. It would have let individuals who will be age 18 at the time of the general election also register and vote in the preceding primary. In presidential years there is eight months between the primary and the general election, so if it had passed, in presidential years over half of all 17-year-olds would have been able to vote in primaries.
Here are the election returns. They are not complete but the margins for those two measures are so overwhelming, it is possible to predict the outcome.