"I'm tired of seeing us lose. I'm tired of seeing us score goals on our own net. I'm tired of seeing inside-baseball infighting," Brown said during a campaign launch speech in his Barrie, Ont., riding.
"I believe with every fibre of my being that if we work together, a strong, stable, majority Progressive Conservative government is within our reach."
Brown, 36, said the Ontario Tories have "lost touch" with grassroots supporters — a contingent Brown said he would give a greater say in shaping party matters such as how it picks policies.
Throughout his speech he drew a sharp line between the way he said the Ontario Progressive Conservatives have been doing things — and what they should do instead.
"Before we can become the party we need to be, we need a clean break from the party we were."
And he's promising to expand the Ontario party's tent to draw in voters from new corners — including youth and new Canadians in urban ridings who he called "conservative at heart."
"Ontario PCs of today must reach out. These relationships need to be founded in respect and fostered constantly — and in some cases we're going to have to build it from square one."
Like the three other candidates, Brown also tried to put space between himself and the party's spring election pledge to slash 100,000 public sector jobs, saying that it scared away potential voters working in frontline services such as nursing, firefighting and teaching.
"We spent a lot of energy going after the public sector, but at a high cost."
Brown has been an MP for Barrie since 2006, and he was a local councillor before that.
The Tories are still reeling after losing the June 12 election, which many in the party blame on the job-cuts promise — an idea from which each of the leadership hopefuls has tried to distance themselves.
The Ontario Liberals wasted no time in going after the newest PC leadership hopeful, saying Brown was among the first to congratulate then-leader Tim Hudak when he rolled out the jobs pledge.
Brown — with a campaign slogan of "For The Win" — becomes the fourth official entrant into the leadership race, which is expected to grow to at least five candidates next month.
The other declared candidates are MPPs Christine Elliott, Vic Fedeli and Monte McNaughton.
Potential candidates for the Ontario Progressive Conservative leadership have until the end of January to file their nomination papers and until Feb. 28, 2015 to sign up new members.
Party members will pick their new leader in early May.
— By Will Campbell in Toronto
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