California voters will decide Proposition 4 on November 3, 2026, a legislatively referred statute that repeals the 1988 ban on public campaign financing and permits state or local governments to establish voluntary programs subject to spending limits, eligibility rules tied to small-donor support, and restrictions barring use of education, transportation, or public safety funds. The measure, advanced through SB 42, faces organized opposition from taxpayer groups citing potential redirection of public resources, while supporters including Common Cause and the League of Women Voters emphasize reduced special-interest influence. With limited polling released and campaigns still in early stages ahead of the general election, trader consensus reflected in the 59.5% probability for rejection aligns with historical voter caution toward new public expenditures and the absence of broad early momentum for passage.