"I believe the future of our party is bright," he wrote in his resignation letter to interim Conservative Leader Rona Ambrose.
"We do not need a new leader to fix us, because we are not broken. We do not need a leader to unite us, because we are not divided. That so many of us want to lead is proof of our shared belief in the party's future."
Erin O'Toole speaks at a press conference in Ottawa on May 12, 2015. (Photo: Sean Kilpatrick/CP)He said he held off on resigning his critic role so he could contribute to a committee study on operational stress injury. His letter said he has started to assemble a team to explore his leadership.
O'Toole had previously run for the interim leadership of the Conservatives, but lost to Ambrose. He thanked her for her contribution to the party.
O'Toole was first elected to the House of Commons in a byelection 2012. He served in Prime Minister Stephen Harper's cabinet as minister of veterans affairs and parliamentary secretary for international trade.
Prior to politics, O'Toole was a lawyer for Proctor & Gamble and an air navigator in the Royal Canadian Air Force.
The Conservatives are expecting to choose their new leader in May 2017.
The contenders, so far
Candidate who has declared, registered and paid the full fee: Michael Chong.
Candidates who have declared and registered: Maxime Bernier; Tony Clement; Kellie Leitch; Deepak Obhrai; Andrew Scheer.
Potential candidates who have declared only: Dan Lindsay; Pierre Lemieux; Adrienne Snow; Brad Trost.
Expected to declare soon: Chris Alexander; Steven Blaney; Erin O'Toole.
Others who have mused about running but not declared: Kevin O'Leary; Rick Peterson; Lisa Raitt.
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