Erin O'Toole has lost a vote to remain leader of the Conservative Party of Canada. 

The party's 119 members of Parliament met virtually today to cast secret ballots after about one-third of them signed a notice that triggered a leadership review.

Ontario MP and national caucus chair Scott Reid said in a statement that 73 Conservative MPs voted to replace him while 45 endorsed him.

As caucus chair, Reid said he did not vote.

Conservative MPs must now choose who will serve as the party's interim leader until the membership elects a permanent leader for the third time since 2017.

New Brunswick MP John Williamson says he would like to be the interim leader.

"I will respect my caucus colleagues. I will listen to our movement," he wrote on social media moments after O'Toole lost the vote.

"I know how to keep us united around the things that matter most to us as Conservatives."

The Reform Act, which has been in place since 2015, allows a party's MPs to trigger a leadership review instead of waiting for the question to be put to the wider membership.

The Conservative caucus is the only one that voted last year to accept the rule as binding.

On Monday night, after news of the coming leadership review came out, O'Toole put out a social media post that painted his dissenters as believing the party should hold more extreme views resembling those of Ontario MPP Randy Hillier and ex-MP Derek Sloan.

O'Toole and his team then started calling different MPs seeking their support. 

Before the vote, Saskatchewan MP Jeremy Patzer also shared a statement with caucus from 21 former Conservative MPs, including former agriculture minister Gerry Ritz, that called for a new leader.

"Erin O'Toole has not only failed to unite the party, his words and actions in recent days have created greater disunity," reads the statement obtained by The Canadian Press.

"It is time for him to step aside for the good of the Conservative Party and the nation."

Former Edmonton MP Kerry Diotte, who lost his in seat the recent election, published his own social media post late Tuesday saying that as a former military man, O'Toole should know when he's lost the battle.

"The writing is on the wall," he said in a post of Facebook.

Garnett Genuis was among the Conservative MPs who were hoping to oust O'Toole. He expressed confidence Tuesday about the likelihood that they had the numbers.

O'Toole, a 49-year-old Ontario MP, took over the reins of the party in August 2020.

The corporate lawyer and Air Force veteran was first elected in a byelection in 2012 in the riding of Durham, a region his father also represented when he was in provincial politics.

O'Toole served as a cabinet minister for veterans affairs in former prime minister Stephen Harper's Conservative government before it fell to the Liberals in the 2015 election.

He then put his name forward to be interim leader but lost. He tried again, this time for the party leadership in 2017, but placed third behind Andrew Scheer.

One of the major knocks critics had against O'Toole began after the 2020 race, where he ran as the "true blue" candidate over former cabinet minister Peter MacKay.

Once in power, O'Toole told party members changes were needed if it hoped to make gains in electorally-important regions like the Greater Toronto Area.

In an attempt to modernize the party and differentiate himself from Scheer — whose social conservative views dogged him in the 2019 campaign — O'Toole promoted his support of access to abortion and LGBTQ rights.

He also embraced carbon pricing, despite the fact that some of his MPs, including many in Western Canada, fought for years against the Liberal government's carbon-pricing mechanism, which the Conservatives called a "carbon tax."

During the leadership contest, O'Toole pledged that it would be scrapped.

During last year's election campaign, O'Toole tried to attract more voters by putting a more moderate stamp on the party.

He also raised the ire of firearms activists and social conservatives by reversing course on promises midway through the race that were inked into his platform when he was being attacked by the Liberals.

Critics like Sen. Denise Batters, who last November began petitioning the party to hold an early leadership review, said his flip-flops damaged his image with Canadians and made him untrustworthy.

Others also point out that O'Toole finished with two fewer seats than Scheer did in 2019, and failed to make gains the party needed in major cities and suburbs.

Since his election defeat, O'Toole has struggled to bring his caucus together on issues like vaccine mandates, with many of his MPs feeling the party needed to take a tougher stand against such policies.

He has also faced pressure to more forcefully oppose a controversial secularism law in Quebec and faced pushback from members of the party's social conservative wing for fast-tracking a government bill to ban conversion therapy for LGBTQ Canadians.

Stephanie Taylor, The Canadian Press