With 97.1 percent reporting, there were 3,359,776 votes for the measure (46.2%) and 3,906,895 votes against (53.8%). The measure lost by 7.6 percent, which is significant but not particularly large for ballot measure.
Prop 19 was more popular than the statewide Republican candidates
Despite this being one of the best years nationally for Republicans in decades, more Californians actually voted for Prop 19 than for the Republican candidates in the top four statewide races. In the Governor’s race, Meg Whitman got only 3,029,919 votes (41.2% of the vote), in the Senate race, Carly Fiorina got 3,094,338 votes (42.5%), in the Lieutenant Governor’s race, Abel Maldonado got 2,812,582 votes (39.4%), and in the race for Attorney General, Steve Cooley got only 3,215,104 votes (45.6%). A quarter of a million more voters supported Prop 19 than they did any of the major Republicans on the ballot.
Support for Prop 19 statewide in California is apparently less “fringe” than support for the Republican Party.
Turnout: demographics is destiny
This was basically on awful year demographically to have a marijuana legalization initiative on the ballot. Midterm elections always see lower youth turnout, and this year was no exception. While there are signs Prop 19 might have slightly boosted youth turnout, nothing can compare to the ability of a presidential race to really bring out young voters.
Clearly, the increase in turnout from older conservatives in this historic GOP wave election was not helpful for Prop 19. In 2008, Congressional Democrats won the national popular vote by around 10 points, and this year, they lost it by around seven. Putting up a ballot measure that polls best with individuals who vote Democratic in that kind of environment is going to face a huge headwind. In a presidential year and/or without a once-in-a-century massive Republican wave, Prop 19 would have done significantly better.