Some 56 per cent of the NDP's candidates in the upcoming spring election are women, the party said Sunday, the first time in Ontario that a major political party has fielded more women than men.

NDP Leader Horwath highlighted the figure at a Mother's Day campaign stop in Toronto.

"We've always as a party been very committed to making sure that our representatives, our candidates that we put out in a campaign, represent the face of our communities," Horwath told a crowd of supporters. She was joined by a number of women running on the NDP's ticket.

Horwath said the party was able to boost the number of women in its rank because seeking out female candidates is woven into local nomination races.

"When people are serious about electing more women, you can put in place procedures and processes that ensure that that outcome happens," she said.

Of the NDP's 124 candidates, 69 — or 56 per cent — are women. That's up from 41 per cent in the 2014 election, when there were 17 fewer ridings in Ontario.

At her own campaign stop, Liberal Leader Kathleen Wynne said that 45.5 per cent of the Grits' candidates are women, while her last cabinet was 46 per cent women. The Liberals still have one more nomination to announce this week.

During the 2014 election, 35 per cent of Liberal candidates were women.

While the Progressive Conservatives did not provide a specific number, a party spokesperson said in a statement, "We have 124 qualified and diverse candidates that are ready to deliver change for the people of Ontario." In 2014, 27 Tory candidates were women.

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"I think increasingly parties are recognizing that women bring diverse voices and life experiences, and demonstrated leadership in the community that is very relevant in a political campaign," said Nancy Peckford, executive director of Equal Voice, a non-partisan organization that works to boost the number of women in public office.

Peckford points out that the NDP has had less trouble with the "incumbency problem" than their rivals. In other words, the NDP has more room for candidate turnover, and therefore more opportunities to bring women into the fold. She adds that while the PCs are slightly behind their primary opponents, they are still "doing very respectably.

"It's certainly far more than we've seen from the federal Conservative party in the past," Peckford said.

"They see and understand the value in electing more women, but they've been less concerted about it."

During her address to supporters, Horwath reiterated a number of campaign platform promises geared toward women. Among them are promises to enforce pay equity legislation and to do away with so-called "pink taxes" — though details on how this would be achieved are scant. The NDP's platforms also includes a series of commitments called 'The New Moms Guarantee,' which would protect neo-natal health care services and boost funding to women's health clinics.