LOS ANGELES (AP) — Marijuana advocates are vowing to push on in California after suffering a defeat at the polls.Voters on Tuesday rejected Proposition 19, which would have allowed adults age 21 and older to possess and grow small amounts of marijuana.Paul Armentano of the National Organization for Repeal of Marijuana Laws says, "Social change doesn't happen overnight."The pro-legalization Drug Policy Project director Ethan Nadelmann says while "There is a sense of people wanting to move into a new policy" they remain "wary of what that change might mean."Roger Salazar, a spokesman for the successful campaign to defeat Prop 19, says the risks of legalizing marijuana "were far greater than the potential benefits," as a way to undercut drug traffickers and free up police.And, Salazar says, "the benefits were far from guaranteed."