It's not the first time the conservative movement has faced a schism, but the prospect of two small-c conservative parties vying for voters in the next federal election has put Conservative parliamentarians on the offensive as they try to refocus after Maxime Bernier's dramatic departure from the party.

Key members of the movement lined up behind Conservative Leader Andrew Scheer on Thursday after Bernier announced he is creating his own party to take on that of his former leadership rival.

Former prime minister Stephen Harper, the man who successfully led the party through rocky political waters after the Canadian Alliance and Progressive Conservative parties merged, said with Bernier gone, the party can move forward united behind Scheer.

"It is clear that Max never accepted the result of the leadership vote and seeks only to divide Conservatives," Harper tweeted.

It is clear that Max never accepted the result of the leadership vote and seeks only to divide Conservatives. His decision today allows the Conservative Party of Canada to move forward united behind our Leader <a href="https://twitter.com/AndrewScheer?ref_src=twsrc%5Etfw">@AndrewScheer</a>. —@stephenharper

Sensing the threat of some Conservative voters jumping ship to the soon-to-be-named Bernier party, his former caucus colleagues went on the attack trying to diminish the Quebec MP's standing among the party faithful.

The strategy? Paint Bernier as an ego-driven politician who's left his longtime colleagues in the lurch.

Tory MPs were quick to brand Bernier as a man only out for himself, the opposite of a team player — going so far as to suggest Bernier has been a slacker as an MP.

"What's his track record?" Alberta MP Michelle Rempel asked reporters.

She said she's fighting the good fight in Ottawa, taking the Liberal government to task over its plan for a national carbon tax and what she says is its mishandling of the asylum seekers file — introducing motions, going on the offensive at parliamentary committees, using the tools of a parliamentarian to hold the government to account.

If he works as hard as he has in the Conservative Party, we don't have a lot to worry about. - Conservative MP Michelle Rempel

She said Bernier has done none of that in the year since he narrowly lost the party's leadership race to Scheer.

"If he works as hard as he has in the Conservative Party, we don't have a lot to worry about," Rempel said when asked if she thought Bernier's new party would be an electoral threat.

Rachel Curran, Harper's former director of policy, said while there's no doubt a robust Bernier-backed party that espouses libertarian values could hurt Conservatives, it's still an open question as to whether Bernier will do the work necessary to get the party off the ground in time for an expected October 2019 election.

"One interesting [question] is whether Bernier has the work ethic and resources to set up and run a new federal party, complete with election candidates, over the next year," she said. "That is no small task. He has support, but does he have the stomach for the thankless grind outside Twitter?"

Even with that uncertainty, Curran said the Liberals must be "breaking out the champagne" at the prospect of two conservative-minded parties competing for voters in 2019.

One interesting Q is whether Bernier has the work ethic and resources to set up and run a new federal party, complete with election candidates, over the next year. That is no small task. He has support, but does he have the stomach for the thankless grind outside twitter? <a href="https://t.co/Dlyf3McotI">https://t.co/Dlyf3McotI</a> —@reicurran

Bernier said Thursday he is leaving the party because, under Scheer's leadership, it has failed to stand up for true conservative principles like dismantling supply management and having a fulsome debate about immigration issues. His recently tweeted views on the latter topic stirred up controversy for the party heading into this week's convention in Halifax.

In his news conference Thursday, Bernier called the party "intellectually and morally corrupt."

"It is afraid to articulate any coherent philosophy to support its positions," he said. "Every public declaration is tested with polls and focus groups. The result is a bunch of platitudes that don't offend anybody, but also don't mean anything and don't motivate anyone.

Former Conservative MP Maxime Bernier explains why he had to leave his "intellectually and morally corrupt" party to strike out in his own. 1:17

"Andrew Scheer keeps talking about his 'positive Conservative vision. But nobody knows what that vision is."

Scheer will have to counter Bernier's claims in his keynote speech to the convention on Friday — arguably the most important speech of his career.

Conservative MPs like B.C.'s Todd Doherty were busy doing their part Thursday to try to challenge Bernier's rhetoric. The fisheries critic used a new hashtag to describe Bernier: #twittertough, a reference to what he considers to be Bernier's tough talk on Twitter compared to his silence in caucus when policy issues were discussed.

Hey Maxime ..remember how I challenged you in an email? Remember how you blamed it all on people around you and how you apologized profusely? How you said you were committed to our team? Wow. You are such a 🐔💩. —@ToddDohertyMP

"A debate on ideas?? Laughable. You had every opportunity to help provide policy ideas as a respected caucus member. You've chosen to put the future of @MaximeBernier before the future of [Canada] #loser," he tweeted.

"I think Max was afraid to come to caucus to have the debate he feels he was not afforded. It's a policy convention..?!? And @MaximeBernier prefers to talk tough on Twitter & runs away. #twittertough."

Even some former Bernier backers, like Conservative Quebec Sen. Leo Housakos, have made it clear they won't be following him.

"The leadership race is long over, and from the moment Andrew Scheer was named leader he has had my full support," he said in a statement to CBC News. "Andrew has shown leadership in allowing all of caucus the opportunity for input on any number of issues. Maxime chose a different route."

Conservative Ontario Sen. Nicole Eaton, another former Bernier supporter, said she was happy Bernier left caucus after his latest "tantrum."

There is nothing like personal ambition, vanity and a lack of discipline to destroy a career. Maxime, the poster child of the above. So much for public service. —@SenNicoleEaton

"There is nothing like personal ambition, vanity and a lack of discipline to destroy a career. Maxime, the poster child of the above. So much for public service," she tweeted.

Despite the negative reaction, the political observers CBC News spoke with Thursday said Bernier is well positioned to pry some voters from the Scheer-led party given his success in the leadership race.

In Bernier's Beauce riding, eight of the nine members of the local Conservative riding association resigned Thursday.

"We've always been there more for Maxime than for the party," riding president Charles Laflamme told Radio-Canada. "The support was for Maxime."

With a file from CBC's Catou MacKinnon