For the second time this week, a poll of likely California voters shows Proposition 19, the measure to make marijuana legal for all adults, ahead – this time by more than 50 percent. In a just-released survey of 2,004 adult residents throughout the state, the Public Policy Institute of California shows Prop 19 leading by a margin of 52 to 41 percent. Earlier this week, the California Field Poll found Prop 19 up 49 to 42. Some details from the PPI poll: Among California’s likely voters, 52 percent…