California voters face Proposition 43 on the November 2026 ballot, a legislatively referred constitutional amendment that would require a two-thirds vote for citizen-initiated local special taxes starting in 2027, closing the Upland loophole while avoiding retroactive invalidation of prior measures. The measure emerged from a June 2026 compromise after lawmakers pulled a stricter anti-tax initiative backed by the Howard Jarvis Taxpayers Association. Public employee unions, the League of California Cities, and special districts have mobilized against it, citing risks to local revenue for services amid ongoing budget pressures. With general taxes still needing only a simple majority and no major recent polling shifts reported, traders assign a modest edge to rejection, reflecting balanced mobilization between taxpayer advocates and government stakeholders.