I agree with Holmes' map. No way it's passing in states like Ohio or Michigan or Arizona or Nevada. You guys realize that Republicans still control those states, right?
If you look at the current polling for those states and project 3.5 years more of increasing public support it's not unrealistic to have initiatives pass in those four states in Nov. 2016, completely bypassing the state legislature and Governor.
And for New Mexico I was counting on a lawsuit at the state Supreme Court like Iowa in 2009. There's potential for that in Wyoming, Indiana, and Pennsylvania too but I didn't include those in my guess.