Support for Amendment 64, Legalizing Marijuana, in the August 8 Public Policy Poll

Colorado support for Amendment 64 compared to general support for legalizing marijuana.

According to today’s Public Policy Poll of Colorado, support for Amendment 64 has grown since the June poll. The amendment, which will be on the Colorado ballot in November, proposes to legalize and regulate growth, possession, and usage of marijuana.

Support has grown by five points to 47-38 from 46-42 in June this year. Independents now support the amendment 58-28, up thirty points from support of 49-40 in June. Democrats favor it 59-22 while Republicans support it 26-61.

15% of voters are undecided on Amendment 64, up from 12% in the June poll.

The poll also posed a more general question, asking whether marijuana should be legal or illegal. Respondents were somewhat more in favor in this situation, supporting legalization 50-42 with 8% undecided. That’s a 2-point increase from June, when respondents supported legalization 49-43.

Support for Amendment 64 and legalized marijuana by political affiliation.

Support for Amendment 64 and legalized marijuana by political affiliation.

The 5-point swing in favor of legalization suggests that Colorado voters are becoming more comfortable with the idea of legalizing marijuana and taxing it in a manner similar to alcohol. This could be a result of the recent pro-legalization ad campaign.

It’s also possible that a lot of this change is a result of statistical noise. The margin of error on both polls was +/-3.5%, so much of the shift could be accounted for by sampling error.

However, the 30-point shift in independent support for the amendment is suggestive. The margin of error for independents is larger than for the overall poll, due to the lower number of independents, but a shift of this magnitude likely represents increasing support in this group.

In addition, little has been heard from groups opposed to Amendment 64. The group Smart Colorado, founded by Weld County District Attorney Ken Buck, opposes the amendment but has only raised $16,000 as of the latest update.

Groups in favor of Amendment 64, including the Colorado Democratic Party and the state medical marijuana industry, have raised well over $2 million.

It is still early. The election is still three months away, and the outcome can easily change during that time. California’s latest legalization attempt, Proposition 19, was leading in polls until late September 2010. It was defeated in the 2010 midterm elections 53.5% to 46.5%.

If support for Amendment 64 continues to grow, it may become law in November. But supporters of the amendment will need to be wary of a co-ordinated opposition by special interest groups. Such opposition has defeated similar measures in Colorado and California in the past.