Surely more than one of the Conservative leadership candidates were tossing and turning in their beds last night, envisioning a worst-case scenario at tonight's debate: Did the moderator just say cheveux or chevaux?

With no simultaneous translation, the candidates will have to know whether such a question is on hair or horses. Cue the cold sweat.

Sure, that example is a stretch. But the bilingual element of tonight's debate injects more unpredictability into this showcase for the 14 declared candidates. It also raises an obvious question: Must one speak French to become the next leader of the Conservative Party of Canada?

Conservatives vote for a new party leader in May 2017. There is some suggestion that all 14 declared candidates believe bilingualism matters, at least a bit. Even those who struggle in French have taken lessons and insist they're trying to improve.

The only exception is a man who says he has not yet made up his mind about running. Businessman Kevin O'Leary made headlines for saying he had failed French in school and wouldn't try to learn now. He did say, however, that it wouldn't matter because he speaks the "the language of jobs."

The candidates' French language proficiency ranges from somewhat pitoyable to pretty much parfait.

Conservative MP Gerard Deltell says the next Tory leader should be able to answer questions in French and converse in the language at a bare minimum. (Justin Tang/Canadian Press)

There's been much discussion ahead of this debate of precisely how well, or poorly, the candidates will perform.

"Who is fluently bilingual? It's very subjective," said Quebec MP Gerard Deltell.

For Deltell, the minimum standard is to be able to answer questions and chat in both English and French. "But three years from now … I want to see my leader do very well in a debate with Justin Trudeau."

The remarkably crowded field of 14 candidates means each individual won't have too many opportunities to weigh in during the Moncton debate. Candidates will face four English questions and four French questions, with 50 seconds to respond per question.

Each of the candidates will be allowed one 30-second rebuttal during the entire two-hour discussion. There will be no simultaneous translation for the candidates or the audience.

CBC debate coverage Watch tonight's debate and then stick around for Rosemary Barton and the Power Panel. It all starts at 6:30 p.m. ET on CBC News Network and livestreaming on cbcnews.ca, YouTube and Facebook.

Deltell doubts the lack of translator will play much of a role, and doesn't think it will affect the results.

"I think that people will recognize people who can recognize a question in French and in English without any difficulties," he said.

French test

Many Conservatives question whether a leadership candidate could hope to become prime minister without a strong grasp of both official languages.

"I think most Conservatives want to put in place a leader that can appeal to the broadest number of Canadians possible," said former Conservative cabinet minister James Moore.

"I think unilingual anglophone Canadians would have a very hard time finding a way to vote for a unilingual francophone candidate for prime minister and I think the reverse is equally true," he added.

Former Conservative MP James Moore says being fluent in both of Canada's official languages is a 'basic core competency' for anyone who hopes to lead the party and the country. (Darryl Dyck/Canadian Press)

Moore points out that about 10 million Canadians say they can speak French.

Quebec is the only place the Conservative party gained seats in the last election. Moore points out that bilingual New Brunswick, where this debate is being held, was also the source of eight seats for the Conservatives in 2011. How well a leader can communicate in both of Canada's official languages, therefore, has implications for any potential road back to power.

French, Moore said, is just a "basic core competency" for anyone who hopes to lead the party and the country.

Those who struggle in Moncton will only be under greater pressure moving forward. The party scheduled five debates at the outset of the leadership race.

The next scheduled debate is Jan. 17 in Quebec City. It will be entirely en francais. Two more bilingual debates will follow.