Fully two-thirds of respondents aged 18 to 34 supported legalization in the General Social Survey. Pictured: Pot revelers celebrate at Denver's annual 4/20 marijuana festival at Civic Center on April 19, 2014. (Brennan Linsley, Associated Press file)

Support for marijuana legalization surging, except Republicans or those over 65

Over 60 percent of Democrats and Independents supported legalizing marijuana in the 2016 General Social Survey, but Republican support stood at only 40 percent

Public support for marijuana legalization surged in 2016, according to data just released from the General Social Survey.

Last year 57 percent of Americans told the survey’s pollsters that they “think the use of marijuana should be legal,” up from 52 percent in 2014.

The numbers from the the General Social Survey — a large nationwide survey conducted every two years and widely considered to represent the gold standard for public opinion research — comport with other national surveys last year, which found support ranging from the upper 50s to low 60s.

But the survey indicates two significant fault lines when it comes to marijuana policy: age and political party. Fully two-thirds of respondents aged 18 to 34 supported legalization in the survey, as well as majorities of those aged 35 to 49, and 50 to 64. But seniors age 65+ stood apart, with only 42 percent supporting legalization.

On the other hand, support among all age groups has risen by similar amounts in recent years. Back in 2008, for instance, only 40 percent of the youngest respondents, and just over 21 percent of seniors, supported marijuana legalization.

Breaking the numbers down by political affiliation tells a slightly different story. In the early 2000s, opposition to marijuana legalization was more or less a bipartisan issue. Only 29 percent of Democrats and 26 percent of Republicans voiced support for legal weed in 2000.

Since then, support for legalization among Democrats and Independents has risen much faster than among Republicans. In 2016 over 60 percent of the former two groups supported legal marijuana. Among Republicans support stood at only 40 percent, a gap of more than 20 percentage points between Democrats and Independents on the one hand, and Republicans on the other.

Moreover, support for legalization among Republicans has leveled off over the past two years, rising just one percentage point since 2016. But support among Democrats rose by three points, and Independents saw a much greater eight-point jump.

Marijuana use, legal or otherwise, remains widespread in this country. Over 33 million adults currently admit to using the drug, according to Gallup. And with victories for legalization in California, Nevada, Maine and Massachusetts last year, roughly 1-in-5 Americans will soon have access to legal marijuana in their home states.

But many lawmakers and law enforcement groups remain resolutely opposed to legalization. In Massachusetts, one of the most reliably Democratic states in the nation, lawmakers lobbied strongly against last fall’s voter-approved ballot initiative, and have been working since then to delay implementation of the measure. Similar efforts are underfoot in nearby Maine.

The Trump administration has been non-committal on its approach to marijuana enforcement. Attorney General Jeff Sessions has been outspoken in his criticism of legalization, but has stopped short of saying that his Justice Department will pursue marijuana cases differently than his predecessor’s.

Meanwhile, Canadian lawmakers are expected to formally announce that nationwide marijuana legalization will be implemented by July of 2018, meaning that for Americans in northern border states, a legal pot fix is just a crossing away.

The General Social Survey was funded primarily by the National Science Foundation and conducted through in-person interviews with a random national sample of roughly 1,900 adults in the spring of 2016. Overall results carry a margin of sampling error of roughly 2.5 percentage points; the error margin for subgroups is larger.