The Trans-Pacific Partnership that became such a hot topic in the dying days of last year’s Canadian election has become a surprisingly big issue in the U.S. presidential primaries too.

The 12-country trade deal covering 40 per cent of the global economy is a signature imitative of a Democratic president, and Republicans have generally championed increased trade, but this time around hopefuls from both parties are sounding skeptical.

Canada’s International Trade Minister Chrystia Freeland told CTV’s Power Play Monday that she’s concerned about the “rising protectionist rhetoric we’re seeing around the world, including in the U.S. election campaign.”

She noted that sixty per cent of Canada’s GDP is driven by trade.

The Liberals have already since signed on to the deal, but Freeland said they will continue to review it before ratification.

She admits that what Canada decides will be moot if the next U.S. president decides to veto the deal.

Here’s a look at where the five remaining presidential hopefuls stand on the TPP, and how some of their positions have shifted over time.

Donald Trump

The leading Republican surprised many last year when he broke with his party’s position and called TPP a “bad deal” that will “send jobs overseas.”

Trump also told 60 Minutes last fall he would also “renegotiate” or “break” the 1994 North American Free Trade Agreement -- the precursor to TPP -- adding that “we need fair trade, not free trade.”

Asked in a debate in November to explain why he disagreed with TPP, Trump responded: “China and India and almost everybody takes advantage of the United States -- China in particular, because they're so good. It's the number-one abuser of this country. And if you look at the way they take advantage, it's through currency manipulation. It's not even discussed in the almost 6,000-page agreement. It's not even discussed.”

Neither China nor India are part of the TPP agreement, which includes Brunei, Chile, New Zealand Singapore, Mexico, Japan, Vietnam, Australia, Peru and Malaysia. In fact, the TPP is being pushed by President Barack Obama as a way to counter China’s growing influence.

Trump’s anti-trade position is proving popular, particularly in the so-called “rust belt” states where NAFTA likely accelerated high-paying manufacturing job losses, even as the unemployment rate in the U.S. continued to fall. Among those polled in March by Pew Research Centre, two-thirds of Trump supporters agreed that free trade agreements have been “a bad thing” for the U.S., compared to 53 per cent of Republicans overall. Among Democrats, only 34 per cent agreed trade agreements were “a bad thing.”

Donald Trump

Hillary Clinton

The Democratic front-runner continues to support NAFTA, although she has switched her position from favouring TPP while in office to opposing the deal during her campaign.

While on a 2012 trip to Australia, when she was Secretary of State, Clinton noted that “our economies are entwined, and we need to keep upping our game both bilaterally and with partners across the region through agreements like the Trans-Pacific Partnership or TPP.”

“This TPP sets the gold standard in trade agreements to open free, transparent, fair trade, the kind of environment that has the rule of law and a level playing field,” she added, pointing to its “strong protections for workers and the environment.”

Last October, while facing a growing challenge from anti-trade Sen. Bernie Sanders, Clinton said she was “not in favour of what I have learned about it.” Clinton added “there are still a lot of unanswered questions,” including about provisions that she said would benefit pharmaceutical companies over patients.

Last month, Clinton told voters in Ohio -- where there are plenty of auto jobs potentially affected by TPP -- that she wants a trade deal with stricter rules on automotive imports. Under the TPP, foreign vehicles could be imported tax-free from countries such as Japan, even if the parts in the vehicles were made in countries outside of the deal, such as China. Autoworkers unions argue that would drive down wages for U.S. workers. Similar arguments have been made in Canada.

Hillary Clinton

Bernie Sanders

The Democratic Senator from Vermont has a long history of opposing both TPP and NAFTA, which he argues drive down American wages.

Sanders issued a statement last May that said TPP “would continue the process by which we have been shipping good-paying American jobs to low-wage countries overseas and continue the race to the bottom for American workers.”

Sanders told a rally in the rust-belt state of Michigan in March that “millions of families around this country have been suffering as a result of disastrous trade agreements,” such as NAFTA, which he hated so much that he introduced legislation in 1993 that would have lowered congressional representatives’ salaries to the pay level of Mexican politicians, or about $35,000.

His anti-trade position may have allowed him to beat Clinton in the auto-making heartland Michigan, where he earned 49.8 per cent of the vote to Clinton’s 48.3 per cent. Exit polling done for The Associated Press found that 60 per cent of Democrats who agreed that “trade is a job killer” had voted for Sanders.

Bernie Sanders

Ted Cruz

Ted Cruz shifted from sounding pro-TPP to saying he is against the deal.

In a Wall Street Journal op-ed last April, Cruz argued that the TPP and a potential trade deal with Europe would “mean greater access to a billion customers for American manufacturers, farmers and ranchers,” although he added that the trade-promotion authority (TPA) that would allow the president to negotiate the deal “must be done right.”

Cruz initially voted in favour of the TPA, but later his switched his vote. He explained in an op-ed after the vote switch that TPA had become “enmeshed in corrupt Washington backroom deal-making.” While he emphasized that he supported free trade “as a general matter,” he could not support the TPA at that point because he believed it allowed “back-door changes to our immigration laws” and “corporate welfare.”

“I have always been for free trade,” he elaborated in a speech the following day at the Heritage Foundation. “I intended to support TPA. Indeed, when it first came up for a vote a couple of months ago, I did support TPA. But unfortunately when the package came back to the Senate floor, it had gone far beyond simply being about trade,” he went on.

In an interview last month with the conservative news website Breitbart, which has nicknamed TPP ‘Obamatrade’, Cruz said he “always opposed TPP.” He also sounded more opposed to trade in general: “We’re driving jobs overseas and the people who are losing out are manufacturing jobs or the steel industry or the auto industry,” he said.

Ted Cruz

John Kasich

Ohio Governor John Kasich is the only presidential hopeful left who still says he favours TPP, but he too has softened his language.

He called the TPP “critical” during a debate last November, arguing that it would provide a counterweight to China’s growing clout. “It's critical to us, not only for economic reasons and for jobs, because there are so many people who are connected to getting jobs because of trade, but it allows us to create not only economy alliances, but also potentially strategic alliances against the Chinese,” he said.

In a debate on CNN in March, he sounded a bit more like Trump, saying his “position has always been we want to have free trade, but fair trade.”

“When countries cheat and they take advantage of us, we need to blow the whistle,” he said. “But we don’t want to lock the doors and pull down the blinds and leave the world,” he went on. “Because frankly, if we do that, prices will go up. People will buy less. Other people will be out of work.”

It’s worth noting that Ohio is a rust belt state, but Kasich still carried it with 46.8 per cent of the Republican vote to Donald Trump’s 35.6 per cent. Ted Cruz got 13.1 per cent.

John Kasich

With files from The Associated Press