Horwath faced some members who were openly calling for her resignation as she spoke to about 250 members of the NDP's provincial council in Toronto, which included riding association members from across the province, MPPs and three former Toronto MPPs who lost their seats.
"We must be clear each and every day about why we want to win, and that means talking about the destination as well as the first steps we want to take to get there," she said in her keynote address.
"We need to do a much better job of broadening our reach than we did in this campaign."
Horwath admitted there were "some real disappointments" with the campaign.
She's been taking heat from some New Democrats for moving to the political centre to try to win votes, upsetting members who felt she abandoned core party beliefs such on social issues as pushing for better pensions.
"The members of our party need to see their values, their priorities, reflected in what we propose," she said.
"We must reach out as broadly as possible within our party and to our allies and our movement when crafting both our commitments and our campaigns."
The New Democrats can take "some comfort" in the fact they increased their vote count to 1.1 million in June, returned with 21 seats _ the same number going into the campaign but four more than the 2011 election, and came second in another 21 ridings, added Horwath.
"I firmly believe that there are the makings of a majority NDP government in them thar numbers next time, if we learn from this campaign and do better in the next one," she said to cheers from the party faithful.
Horwath will face an automatic leadership review at the NDP's annual meeting in November, but appeared confident of her chances after talking with party members at their meeting in Toronto this weekend.
"There was criticism but there was also some praise, and so it was a fair and open discussion and very necessary," she told reporters afterwards.
"We have a very democratic party and we have a process that automatically creates a review of the leadership at every convention, and so in November the members will have their decision."
The NDP's Socialist Caucus has been circulating a petition saying Horwath had no mandate to "turn the party to the right" with a campaign it claimed alienated social justice advocates and labour unions and should resign.
Veteran New Democrat MPP Cheri DiNovo attended a recent meeting of the socialist caucus, but said Saturday she didn't know they were going to be talking about demanding Horwath's resignation.
DiNovo also said she has not been chastised by the leader's office or other New Democrats for criticizing the campaign platform and strategy, and said the Ontario party should follow the lead of the federal NDP.
"We're seeing the demand for a $15 (an hour) minimum wage federally. Wow, that's core NDP DNA stuff, really socially progressive," said DiNovo.
"That's what I think the rank and file wants to see in our party."
However, Horwath would commit only to pushing for "a living minimum wage," and would not say what amount that should be.
Horwath earned cheers when she said the New Democrats were the only real opposition party because the Progressive Conservatives will be tied up in a leadership battle for the next year, and predicted the Liberals wouldn't keep their campaign promises.
"We are the only functioning opposition party at Queen's Park for the foreseeable future, we are going to do our job with passion and commitment and determination," she said.
"We're going to hold their feet to the fire when they break their promises, because Ontario deserves a better government than that.
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