Young voters will be key to deciding whether there is a 'yes' vote for the cannabis referendum, a pollster believes.
The latest Research New Zealand poll set out to gauge how New Zealanders plan to vote in the upcoming cannabis referendum that could result in the legal sale of the drug with government controls.
Research NZ managing partner Emanuel Kalafatelis, who has been undertaking regular polls on the topic this year, told Sunday Morning he had felt a positive outcome was "a lost cause" but he was now revising that opinion.
The latest results showed that almost half of those polled (46 per cent) now say they will vote in favour of legalising recreational cannabis - compared with 40 per cent not in favour.
The balance are undecided or prefer not to say, although that number has reduced from 25 per cent earlier in the year.
"The reason why we are seeing support increasing now is that the number of people sitting on the fence is declining," Kalafatelis said.
That could be attributed to greater media coverage as well as advertising both for and against legalisation.
Those most in favour are at the younger end of the age spectrum, those not in favour are at the older end.
"It's going to come down to getting those younger voters, who traditionally don't vote in general elections, to actually turn up to the polling booth and vote because they are the people who are most in support of the legislation in comparison to older voters.
"If they don't turn up, then this isn't going to get over the line."
By Friday, 75 per cent of 18 to 25-year-olds were enrolled, compared to 71 per cent overall in the previous election.
Participants were asked about their reasons for their opinion.
At least half those who supported legalisation said the taxes raised by legal sales could be spent on health and education about use of the drug, and they also believed it would free up police to focus on other crimes.
Opponents' reasons include that smoking is bad for your health, cannabis is a gateway drug, and they had general concerns about users' health and safety.
There is also concern about the impact of cannabis use on young people's mental health, as well as worry that people might drive while "stoned".
Recreational and medical use were regarded as the same thing by many of those who will vote no.