The format didn't allow for any direct attacks on fellow candidates, but the twelve contenders for the Conservative Party of Canada leadership found quite a bit to disagree on during their first official debate in Saskatoon.

Party members won't vote on their next leader until late May. But this first viewing of the large field — two women and 10 men for now — set the tone for the next six months of campaigning.

Ontario MP Michael Chong joked that it would be like a debutante coming out at a ball, as the candidates introduced themselves and their positions. But the fast-paced format more closely resembled an express tour of who intends to stand for what in this contest.

In the process, real differences of opinion emerged on the merits of carbon taxes, immigration strategy and the best way to support the agriculture sector.

Debate moderator Kaveri Braid, a former journalist and political strategist, posed twelve questions: eight written by the party and four identified as coming from party members. Every candidate could respond very briefly to each question.

The early economic questions found candidates broadly agreeing on the need to control government spending, cut internal trade barriers and spur economic growth by lowering taxes — although not necessarily in the same way or to the same extent.

All the candidates said they support free trade, although several admitted that Tuesday's U.S. election result, including the election of trade-skeptic Donald Trump as president, likely means the Trans-Pacific Partnership, a 12-country Asia-Pacific trade pact negotiated while the Conservatives held government, may now be dead.

The 12 candidates in race to become next conservative leader <a href="https://twitter.com/hashtag/cdnpoli?src=hash">#cdnpoli</a> <a href="https://twitter.com/hashtag/CPCLdr?src=hash">#CPCLdr</a> <a href="https://twitter.com/hashtag/hw?src=hash">#hw</a> <a href="https://t.co/xwuMx2h1ob">pic.twitter.com/xwuMx2h1ob</a> —@HannahThibedeau

Lisa Raitt said that news Canada may be willing to re-open the North American Free Trade Agreement (NAFTA) gave her pause and she wanted to know what the Trudeau government was planning.

"We need to win because trade matters can't wait for three years," Lisa Raitt said. "I believe that I can win in 2019."

Kellie Leitch emphasized repeatedly during the debate that she would have a good working relationship with Trump.

"We have some common ideas," she said, although she later clarified to reporters that she never actually endorsed him. "I plan on being tough on him when it comes to NAFTA."

In a Tuesday night email to her supporters, candidate Kellie Leitch said "our American cousins threw out the elites," calling this an "exciting message and one that we need delivered in Canada as well."

Conservative leadership candidate Kellie Leitch, left, stuck to her call for extra screening of newcomers to Canada based on 'Canadian values,' despite criticism from Lisa Raitt (right) and others who want to focus on different issues. (Liam Richards/Canadian Press)

'Quit playing politics with this file'

Leitch, as well as Steven Blaney — who wants to ban wearing the niqab — stuck with their focus on protecting "Canadian values" during the debate.

"Two-thirds of Canadians have said they agree with me on that policy and that transcends party politics," Leitch said. "I'm out talking to Main Street and that's what I'm hearing."

"I want to make sure that new Canadians understand our core principles," Blaney said. "The more they get it, fast, the best they will integrate."

Other candidates disagree, including Chong, who issued a statement Wednesday calling Leitch's policy of singling out newcomers for more screening "a losing strategy."

"The right approach is to quit playing politics with this file," he said during the debate.

While he too believes in paying attention to the concerns real people face in their everyday lives, Chong told CBC News earlier "anybody who wants to mimic Donald Trump's election tactics is not being helpful to building a big tent Conservative movement."

Conservative leadership candidate Michael Chong repeatedly plugged his plan for wide-ranging tax reforms and an ambitious carbon tax policy. Most other candidates oppose a carbon tax. (Liam Richards/Canadian Press)

"That's her debate. That's not my debate," Maxime Bernier told CBC News. "We have strong screening here in Canada."

"Maybe Leitch thinks she is running for the Republican Party," he quipped to reporters afterwards.

Deepak Obhrai reflected on his own experience as an immigrant and said that being referred to as a good example of immigration by people in his party disturbed him and made him feel like a mutant.

"If somebody wants to wear niqab and be marginalized, it is their problem. I really don't give two hoots," he said.

"A Canadian is a Canadian is a Canadian," the veteran Alberta MP said, borrowing a line from now-Prime Minister Justin Trudeau during the last election.

"The road that Steven Blaney and Kellie Leitch are going down is catastrophic," Vancouver businessman Rick Peterson, who expects to join the race next week, told CBC News earlier. "There are no Conservatives in urban ridings in Canada because of that."

Andrew Scheer said his party had to have a positive, inclusive message.

"I will not say anything in this leadership race to further my chance in 2017 that might risk our chances in 2019," he said.

'More a political issue than science'

More differences surfaced during a question on reducing greenhouse gas emissions.

Chong centres his platform around a revenue-neutral carbon tax plan, which he said has been reviewed by economists at four Canadian universities and found sound. Others piled on to slam it.

Obhrai said a carbon tax was "not a Canadian solution."

Erin O'Toole said pursuing it was "lazy public policy" for the Liberal government.

Chris Alexander said it was regressive and hurts vulnerable Canadians. Leitch said that she would abolish it the day she becomes prime minister.

"It is economic madness when other countries around the world are abandoning the idea of a carbon tax," Scheer said. "We need to fight this."

Brad Trost said the concentration on climate change was not needed, calling it "more of a political issue than a science issue." But he gave Chong credit for at least being clear on his policy. Although he did not think it should be a priority, Trost pointed out that other candidates did not say what the cost of their emissions reductions plans were.

Conservative leadership candidate Maxime Bernier said he was proud to argue against the supply management system that regulates prices in the Canadian dairy, egg and poultry sectors. His position runs contrary to policy Conservatives endorsed at their convention in Vancouver last spring. (Liam Richards/Canadian Press)

Bernier found himself isolated for his position that Canada should end its supply management system for the dairy, egg and poultry sectors, something he believes inflates prices. He said he is proud to advocate for consumers and not this cartel.

"Maxime, your plan is a disaster, blinded by ideology" fellow Quebec MP Steven Blaney told him, accusing him of financing his campaign on the back of farm families.

"Our membership voted in Vancouver that we would support supply management," Leitch said. "Unlike other candidates in this race I respect the party membership and the decisions the party membership has made."

Large field may grow

The candidates who filed the required paperwork and paid at least an initial $25,000 installment to meet last week's registration deadline for this first party-organized debate were:

Chris Alexander.

Maxime Bernier.

​Steven Blaney.

Michael Chong.

Dan Lindsay.

​Kellie Leitch.

​Deepak Obhrai.

​Erin O'Toole.

Lisa Raitt.

Andrew Saxton.

Andrew Scheer.

​Brad Trost.

Peterson has nearly finished collecting the signatures required and could join the next scheduled debate. Former MP Pierre Lemieux has also declared his candidacy but not yet filed his papers.

Businessman and television personality Kevin O'Leary attended the debate, as he continues to mull his decision whether to support any of these candidates or run himself.

Businessman Kevin O'Leary (left) is still considering whether to enter the Conservative leadership race or support another candidate. He sat just behind the debate moderator Wednesday, appearing frequently on camera as a result. (CBC News)

Candidates have until February to enter the race.

The party is hosting five leadership debates: this event in English, a bilingual debate in Moncton next month, and three more, one of which will be in French with no translation provided, a test of their language skills.

Some riding associations are organizing additional events, such as one planned in south Ottawa Sunday featuring nine candidates.