Maybe somebody else here knows. The CA SecState website (old material, talks about getting signatures to trigger a recall election) talks about "Yes" representing a majority of voters. If each ballot represents a voter, then the default is "No," i.e., "NO" is counted even if the person does not punch the "NO" chad, and a YES vote requires an affirmative act on the part of the voter.
Thanks for your input -- best of luck to you and everybody else in the great sate of California.