The premier-to-be said she feels a "special responsibility" to young gay people who are looking for a more accepting world, but she's not a gay activist and doesn't plan to spend the next few months talking about her sexual orientation.
"It is important to me that young people and people who are frightened see the possibilities," she said. "And if I can help people to be less frightened, then that's a wonderful, wonderful thing."
But for her, the real historic moment is becoming the sixth woman premier in Canada.
"We've wondered about why we haven't had a higher percentage of women in legislatures and in Parliament," she said. "Well, maybe now we're reaching a critical mass."
Wynne's victory as Ontario's Liberal leader and next premier is a significant historic moment for the country, said Helen Kennedy, executive director of Egale Canada, a national lesbian, gay, bisexual and transgendered human rights group.
But having an out, progressive woman to lead the province is something to be proud of too, she said.
"It sends a strong message to those young kids who are cautious and nervous about their own journey with respect to their sexual orientation and gender identity, that you can do it if you're true to yourself," Kennedy said.
It's also important for the parents of LGBT children to know that their kids can be and do whatever they want, regardless of their sexual orientation or gender identity, she added.
It's a "giant leap forward" at a social and cultural level for Ontario, said Bryan Evans, a politics professor at Toronto's Ryerson University.
"But at the end of the day, I think issues of identity are secondary to 'Are we electing somebody who can do the job and move Ontario forward in a difficult time'," he said.
Wynne, 59, was married to a man and had three children before she came out at the age of 37. She is now married to her longtime partner, Jane Rounthwaite.
While her sexuality wasn't a secret at Queen's Park and Wynne didn't shy away from it, it wasn't something she spoke about publicly in her work as a cabinet minister.
She didn't shrink from questions Sunday about a new sexual education curriculum for elementary schools, saying she intends to revamp it nearly three years after some controversial changes forced Premier Dalton McGuinty to put it on hold. But she'll consult with parents and education groups in putting a new curriculum together.
Homophobia always comes up in her campaigns and did in this one too, with a Toronto newspaper editorial asking if Ontario is ready for an openly gay premier.
The question is posed to her as an electability issue, but it underestimates Ontarians to assume that sexual orientation is going to determine how they vote, she said.
And Ontario is ready for a gay premier, Wynne told Liberal delegates in a rousing speech Saturday at the leadership convention.
"The province has changed, our party has changed. I do not believe that the people of Ontario... hold that prejudice in their hearts," she told the crowd.
Wynne also thanked Rounthwaite in her victory speech Saturday for being "on the front line" during the gruelling three-month campaign, as the crowd erupted in cheers, chanting "Jane! Jane! Jane!"
Wynne may have a difficult road ahead of her, said Kennedy.
"I'm not naive enough to think that homophobia and transphobia are still not alive and well in Ontario and around the country," she said. Wynne can work around it, but she'll need a lot of support from all the opposition parties.
But Wynne, who's served as minister of education, aboriginal affairs, municipal affairs and transportation, also has a solid reputation as a politician who can prevail even when the odds are stacked against her.
The former school trustee and Harvard-trained mediator beat a Conservative cabinet minister when she was first elected to the legislature in 2003. Then in 2007, she trounced Conservative leader John Tory on his own turf in the Toronto riding of Don Valley West.
Despite trailing in second place behind her rival Sandra Pupatello in the leadership race, Wynne managed to pull ahead at the convention and win.
Wynne rose to the top job because of her ability to lead and who she is as a person, Kennedy said.
"I think the first thing that people will judge her on is her ability to get the job done," she said.
"I think she will be judged ... on her policies, before they will judge her on her sexual orientation. It is a part of who she is, but it's one part."
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