Voters were fed up with the scandal-plagued Liberals last June and wanted a change in government, but didn't like what the PCs were offering under leader Tim Hudak, Brown told the audience.
"Let's be honest with ourselves, they didn't just look at Tim Hudak but they looked at the establishment in our party," he said. "They looked at you Christine, as deputy leader, standing shoulder to shoulder with Tim Hudak and the 100,000 job cuts."
The shot at Elliott by Brown, a federal MP and the only one of the five PC candidates who is not a member of the Ontario legislature, came in the closing statements of the debate, eliciting some boos from the audience and a quick retort from his target.
"I would like to start by dispelling Patrick's myth that I knew anything about the 100,000 job cuts before the election," said Elliott. "Let me say categorically that neither me nor any of my caucus colleagues had any knowledge of it, and that's why our party needs to change."
After the Conservatives' fourth consecutive election loss last June, most defeated PC candidates and re-elected MPPs insisted they were unaware of the job cuts plan until Hudak announced it in the first week of the campaign, a fact disputed by senior officials in the leaders' office at the time.
Most Tories admit it was the job cuts proposal that turned unions against the party and helped the Liberals be returned with a majority government.
Brown called the idea "crazy" and a "disaster" for the party.
For most of Monday's debate the candidates treated each other with kid gloves and saved their harshest barbs for the Liberal government and its economic and energy policies, with several promises to end subsidies for wind turbines.
The PC leadership hopefuls all agreed that getting Ontario's fiscal house in order was a top priority, with vows to bring back financial responsibility after the Liberals ran up a $12.5 billion deficit.
There was lots of talk about the need to lower energy prices to keep companies from leaving Ontario for cheaper power in other jurisdictions.
All the candidates attacked the Liberals' proposed provincial pension plan and a planned carbon tax as exactly the wrong ideas for the economy, with finance critic Vic Fedeli offering a new promise to eliminate income taxes on young people.
"I have pledged to introduce a policy of no provincial income tax for anyone 25 years old and under," said Fedeli. "This is a policy that will help put young people to work."
Ottawa's Lisa MacLeod said the Conservatives lost the support of police because they stopped talking about law and order issues, and said the party must also show more of its environmental policies, saying people need to know that being Tory blue doesn't mean you can't also be green.
Candidate Monte McNaughton said he was the only one to openly oppose the Liberals' plans to update Ontario's sex ed curriculum this fall, but Brown also spoke against the plan.
Brown also lashed out at his colleagues for not making real efforts to bring various ethnic groups into the party, saying he never sees provincial Conservatives at many well attended multicultural events in southern Ontario where federal Tories find support.
"It's about showing up," said Brown. "We as federal Conservatives make sure there is not a cultural event that we do not have a representative at. What I find alarming is not on one of those occasions have I seen a provincial Conservative."
For the most part the candidates shied away from criticizing fellow Conservatives, in part because of the party's preferential balloting system for their leadership vote in May.
They don't want to upset supporters of rival campaigns because PC voters will be picking their second and third choices at the same time as they cast their vote for the preferred leader.
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