Earlier this month, a mere year into the race to choose a new leader for the Conservative Party, Michael Chong declared it was "time to get serious."

"It is time to say 'Enough!'" Chong said in a note to supporters after a group of young men wearing Make America Great Again hats were reported to have profanely heckled a reporter at a Conservative debate.

"No more catering to anti-immigrant sentiment ... Or discussions on climate change that don't actually include any plans to address climate change. Or an obsession with screening immigrants for somebody's perception of what Canadian values are."

Conservatives, Chong ventured, need to be a "credible, serious" party, not one that tries to "fool people with shiny objects or appeals to their baser instincts."

Of course, it is Michael Chong's opinion that the Conservative Party would be most credible with Michael Chong as its leader.

Chong was perhaps the loudest Conservative critic of Kellie Leitch's proposal to screen visitors for Canadian values. He was the only Conservative MP to vote in favour of a Liberal motion to study Islamophobia. And his proposal to price carbon emissions is the most substantial attempt by a Conservative leadership candidate to confront climate change.

Coincidentally, or consequently, he appears to be a long shot to become the next Conservative leader.

"It is time for adult conversation," Chong concluded. "Many of my fellow leadership contenders seem to be running simply to be leader of our party. I am running to be leader of our country."

Therein lies Chong's real argument: not merely that the Conservative Party should be serious and credible, but that it should also try to win — and that it's in danger of setting itself up to lose.

CBC will have live coverage of the final Conservative leadership debate tonight at 6 p.m. ET on CBC News Network and livestreaming at cbcnews.ca/politics and Facebook , followed by a special Power & Politics at 8 p.m. ET.

Beyond the choice of the next leader, that might be the most interesting question about the Conservative Party: will it sound anything like Michael Chong?

Or has the die been cast for a Conservative Party that will be skeptical, at best, about widespread immigration and loudly opposed to taking serious action on climate change?

Candidate positions

Chong didn't name any of the candidates he had in mind. But when the candidates gather in Toronto tonight to debate each other one final time before voting begins Friday, it's entirely possible Chong will once again hear things that disappoint him.​

Leitch's values-screening has been the most talked-about proposal of the campaign, but she hasn't been alone in fretting about those who arrive at Canada's door.

Maxime Bernier, a presumptive front-runner, has suggested, obliquely, that "radical proponents of multiculturalism" want to "forcibly change the cultural character and social fabric of Canada" and proposed reversing the Liberal government's increases in the annual intake of immigrants.

Brad Trost has vowed to suspend immigration from countries or regions that "support, encourage or harbour terrorists or Islamic extremism."

Steven Blaney has proposed banning the niqab from the public service and using the notwithstanding clause to protect the ban from any judicial injunction.

Federal conservative leadership candidate Kevin O'Leary has expressed concern about the rise in asylum seekers crossing into Canada from the U.S. (Chris Young/Canadian Press)

Kevin O'Leary denounced Leitch's screening proposal and has held up his own family's history of coming to Canada to explain why he won't follow U.S. President Donald Trump's approach to immigration, but he has since attacked the rise in asylum seekers crossing into Canada from the U.S.

And on that he has been joined by Leitch, Bernier, Trost, Andrew Scheer and Erin O'Toole.

O'Leary, Bernier and Trost have proposed using the notwithstanding clause to suspend the legal rights afforded to such refugee claimants. Bernier has suggested he'd dispatch the military to patrol the border.

​Meanwhile, opposite Chong, there is loud and widespread opposition to the notion of pricing carbon emissions, with little in the way of proposed alternatives. (Though only one candidate, Trost, is willing to say he doesn't think climate change is a serious concern.)

Most of the above could be viewed as an extension of themes and ideas from Stephen Harper's time as leader.

It was Harper's Conservatives who eliminated health-care services for refugee claimants, tried to ban the niqab during citizenship ceremonies, proposed a "barbaric cultural practices" hotline and sought to revoke citizenship from dual nationals convicted of terrorism-related offences.

And it was the former Conservative government that couldn't bring itself to explain how Canada should meet its international climate targets, opting instead to complain about the costs associated with other parties' plans.

Of course, those Conservatives were also reduced to 99 seats in the last federal election, opposite a Liberal leader who happily embraced the notion of diversity and vowed to put a price on carbon.

Looking ahead to 2019

That result might have been expected to prompt a Chong-esque recalibration. Instead, Chong seems to be on his own.

Does that portend electoral doom?

Frank Graves of Ekos points to polling data from recent years that shows a significant number of Conservative voters question the seriousness of climate change and think the country is accepting too many immigrants. He says 57 per cent of Conservative supporters approved of Trump's victory.

Those voters might not be enough on their own to put Conservatives back in government, but Graves suggests they could be added to voters more concerned with economic or social issues. Maybe the party ends up harnessing the populist backlash that is evident elsewhere.

David Coletto of Abacus Data says the burgeoning pool of millennial voters might avoid a party that doesn't seem serious about climate change. But he thinks there could be an audience for an economic argument that questions immigration.

The Conservatives might give themselves room to criticize Liberal shortcomings on immigration and climate change. Or they might turn off moderate voters while chasing the party's base.

In the meantime, whereas Chong might have diminished the differences between Conservatives and Liberals, a Conservative Party that is critical of increased immigration and diversity and not particularly interested in Canada's climate targets could polarize the public debate.

Unless, of course, the next Conservative leader decides Chong is on to something.