A new Gallup poll released yesterday revealed that 58% of Americans support legal marijuana use. Sentiment peaked at 58% in 2013 as well, before dipping sharply in 2014 and then recovering.

This represents a high point in Gallup’s 46-year history of polling on legal marijuana use. Back in 1969, only 12% of Americans backed legalization; 1977’s polling revealed a 28% peak in support which dipped until 1993. Since then, we’ve seen a steady increase in support.

marijuana use support october 2015

Stereotypes fall into place as far as demographics are concerned. Younger people, Democrats, and independent voters are more likely to support legalization, whereas older voters and Republicans are less likely to support it.

Interesting point: support has (predictably) increased amongst 18-34 year olds from 20% in 1969 to over 70% today, but it has also increased—at a similar rate—amongst older Americans and senior citizens.

Gallup’s takeaway on this point? Among all age groups, the increase in support has been proportionately greater over the last 15 years than it was between any of the earlier time periods.

More from Gallup:

These patterns by age indicate that one reason Americans are more likely to support legal marijuana today than they were in the past is because newer generations of adults, who are much more inclined to favor use of the drug, are replacing older generations in the population who were much less inclined to want it to be legalized.

But the increase in support nationwide is also a function of attitude change within generations of Americans over the course of their adult lifespans. Gallup’s historical data allow for a look at how views on marijuana legalization have changed over time among independent samples of those in the same birth cohorts. For example, Americans who are aged 65 through 79 today — born between 1936 and 1950 — are more supportive of making marijuana legal in 2015 than those born in the same years were 15, 30 and 46 years ago. This birth cohort’s support has increased from 20% in 1969 to 29% in 2000/2001, and is 40% today.

Supporters and attitudes have changed—and yet we’re not seeing nearly as persuasive an argument behind marijuana legalization as we saw with gay marriage, which saw similar change in sentiment amongst similar demographic groups. We now have multiple states making use of their own legislatures to legalize and regulate marijuana use within their own borders, and a federal government that has essentially abandoned federal law governing its use and sale.

Health care, education, and the economy have dominated in the minds of voters so far this cycle—will legalization (and to a greater extent, state sovereignty) take its place in the mix? Stay tuned.

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