California Assembly Constitutional Amendment 21
(ACA 21) was proposed for, but ultimately did not qualify for, the 2010 ballot
as a legislatively-referred constitutional amendment
. It was sponsored by Charles Calderon
, a Democrat
in the California State Assembly
ACA 21 would have changed the California Constitution by requiring that initiated constitutional amendments proposed by the people require a two-thirds majority of the votes cast for passage instead of the current simple majority.