Roughly one-third of Canadians aren't convinced same-sex couples should be allowed to marry, according to a new poll released days ahead of Vancouver's massive Pride celebration.

Just 64 per cent of respondents in the latest Research Co. survey agreed that same-sex marriage "should continue" in Canada, where the practice has been legally recognized nationwide since 2005.

That's compared to 15 per cent who said gay couples should only be allowed to form civil unions, and 10 per cent who argued they shouldn't have "any kind of legal recognition."

Another 11 per cent of respondents could only say they're not sure where they stand on the issue.

"It shows that there's a lot of work that needs to be done," said Mario Canseco, Research Co. president.

"I was pleasantly surprised that the number of supporters was almost two-thirds, but you still see about 25 per cent saying go back to civil unions or don't (recognize) anything."

While there is no serious challenge to gay marriage in Canada – Andrew Scheer voted against legalization in 2005 but has promised not to reopen the issue – it recently returned to the forefront after the Anglican Church of Canada rejected a proposal to bless same-sex unions across the country.

The vote drew widespread criticism and disappointment, much of which came from within the church.

Research Co. found support for same-sex marriage varied from province-to-province; it was strongest in Saskatchewan and Manitoba, where 77 per cent of respondents said it should continue, and weakest in Atlantic Canada, where only 60 per cent agreed.

Gay marriage was also slightly more popular among younger Canadians than older ones, which is one reason Canseco believes the numbers will continue to tick up as time goes on.

"Millennials are not holding onto the prejudices of other generations on this," he said. "Is it going to get to 100 per cent? I doubt it, but it's definitely a situation where it's better than it was before."

Pollsters found a similar split in support for school lesson plans that cover sexual orientation and gender identity, like B.C.'s SOGI 1 2 3 program.

Research Co. also asked Canadians whether they believe people who identify as LGBTQ2+ are born that way. Only 45 per cent said people are born LGBTQ2+, while 24 per cent saw it as a choice and a whopping 31 per cent said they're not sure.

Canseco said when it comes to some of these issues, there are many straight and cisgender Canadians who feel legitimately confused.

"I think there's genuinely people who can't make up their minds," he said. "Maybe you don't know anyone who's LGBTQ or you've never been to a same-sex wedding and you're genuinely confused about this issue."

Research Co.'s online survey was conducted from July 15-17 among 1,000 adults in Canada. Polls of that size carry a margin of error of plus or minus 3.1 percentage points, 19 times out of 20.