OTTAWA -- Pierre Poilievre and Erin O'Toole are both going to run for the Conservative leadership, CTV News has learned.

Poilievre has been a member of Parliament in Ontario since 2004 and is currently the Conservative Party's finance critic. O’Toole, who and already has one failed leadership bid under his belt from 2017, has been elected since 2012.

Speculation began to circle about both Poilievre and O'Toole's potential leadership bids shortly after Andrew Scheer's Dec. 12 resignation. As journalists pressed Poilievre for an answer four days later, he refused to rule out a bid.

"It's too early to say what's going to happen. There will be lots of people who will put their names forward. What I do know is that we need someone who will stand up, fight back, and win," he said at the time, while pounding his fist on the podium.

O'Toole is already rallying his team and volunteers, according to a source with first-hand knowledge of his bid.

John Baird, who has previously served in multiple high-profile roles as a member of Stephen Harper's cabinet, will run Poilievre's campaign.

Candidates hoping to have a shot at winning the race will need to decide whether to run by mid-January, according to Lisa Raitt, who is co-chairing the leadership race organizing committee. The Conservative Party is choosing its leader on June 27. Raitt has said the short race time was chosen as a result of the current minority government, which could fall and trigger an early election. In that case, she said, the new leader would need to be prepared.

As for who else might run for the leadership, multiple names have emerged as politicians and pundits carve out the names of the people they hope to see run – including Rona Ambrose and Peter MacKay.

Sources from Ambrose's camp told CTV's Evan Solomon that the former Conservative interim leader has been seriously considering a run.

"She's struggling with a decision because she knows where the party is at [and] it's her instinct to jump in and help," the source told Solomon.

Former NDP Leader Tom Mulcair has said former Quebec premier Jean Charest is considering a bid. High-profile Tories Michelle Rempel Garner and Candice Bergen also have yet to shoot down a potential run.

Failed 2017 Tory leadership candidate Michael Chong and prominent Quebec Conservative Gérard Deltell are also among those whose names keep coming up in speculative circles, but none have formally announced whether they'll try to take over the party's helm.

Bryan Brulotte, CEO of MaxSys Staffing and Consulting and longtime political organizer, has already officially launched his own leadership campaign.