The company first started asking the question in 1979, at which point just 27 per cent said they were in favor of legalization.
Democratic Rep. Earl Blumenauer of OR, who has introduced a bill to end pot prohibition this year, said legalization backers had made "amazing progress" in the last year, partly by doubling the number of states that allow the recreational use of marijuana.
Medical marijuana is legal in 30 states and Washington, DC, while five states will vote to legalize recreational marijuana - and another four for medicinal use - in November.
"I'm not sure we're going to be a better, healthier nation if we have marijuana sold at every corner grocery store", he said, though noting that "states can pass whatever laws they choose".
The lift in support comes as many states have legalized marijuana in some form, CBS News noted in the poll released on Thursday. Although approval fluctuated somewhat after that, a number of surveys conducted over the past year have shown support for legal recreational marijuana crossing the 60 percent threshold, with fewer and fewer Americans expressing opposition. Marijuana is still illegal under federal law. A total of 29 states have legalized marijuana for medical purposes, with the latest addition coming this week in West Virginia. The poll showed that 65 percent think that marijuana is not as risky as other drugs, and 23 percent believe that the legalization of the drug would lead to crime.
Lauren McDowell, a 32-year-old who started using marijuana to treat pain after a 2014 auto accident, agrees it makes no sense to criminalize pot for more than another year.
The legal limbo is expected to last at least until July 27, the deadline set by Attorney General Jeff Sessions for a Justice Department task force to review USA marijuana policies.
More than half of all states have legalized medical marijuana. No group supports enforcement in states where marijuana is legal.
QU said that is "also the highest level of support in any national poll". If they're forced to choose between defending Trump on the one hand, though, and siding with his pro-pot critics on the other, it wouldn't surprise me if they shift a bit against legalization. The dynamics of polarization being what they are, any backlash from the pro-weed side is apt to make Republicans circle the wagons around the White House, triggering a counter-backlash. GOPers were split 46/49 on legalizing weed in CBS's data, tantalizingly close to majority support.