Political third-party groups made their presence known during Game 5 of the NBA finals last night with big ad buys — taking advantage of a chance to beat the buzzer and reach a massive audience before new spending restrictions kick in at the end of the month.

The Conservative Party has twice run ads introducing leader Andrew Scheer to playoff audiences. Millions of Raptors' fans who tuned in to Monday night's heart-pounding loss against the Golden State Warriors also saw a series of commercials from third-party advertisers.

"If you're looking to have an impact, then you're best to play in large sandboxes," said Unifor President Jerry Dias. "And so that's what we're doing."

His union bought two ad spots that aired during the game, urging voters to choose a government that "will unite us, not tear us apart."

Dias isn't hiding the goal of the ads: to spook Canadians away from voting for Scheer and the Conservatives.

"The ad is to make sure that there is an incredible consciousness in this country about the shape of our politics," he said.

"I'm concerned if we end up with a federal Conservative government, that all we end up with is another austerity program. Cuts, cuts, cuts."

A group called Shaping Canada's Future ran an ad during the game that closely mirrored the 'job interview' attack ads the Harper Conservatives ran in 2015.

Shaping Canada's Future, which describes itself as a "free enterprise oriented" group, even hired the same actors for their spot.

This time, the actors are shown conducting a job assessment of Prime Minister Justin Trudeau and concluding that he was "never ready" — a riff on the Conservative's "just not ready" tagline of four years ago. (Unlike the 2015 ad, this one makes no mention of Trudeau's hair.)

No one from Shaping Canada's Future returned CBC's calls, but corporate records show it's helmed by Douglas Nelson and based out of Calgary.

According to Elections Alberta, a Douglas Nelson was also the contact for the group Shaping Alberta's Future and the chief financial officer for Jason Kenney's winning campaign during the 2017 UCP leadership race.

Shaping Alberta's Future received tens of thousands of dollars in corporate funding during Alberta's recent election, including contributions from the oil and gas industry.

Engage Canada has union ties

Leaning to the other side of the political spectrum is Engage Canada, which ran two short ads during the game painting Scheer as a "yes man" to Ontario Premier Doug Ford.

Engage spokeswoman Tabitha Bernard wouldn't say who runs the group, but former NDP strategist Kathleen Monk — now a principal with the Earnscliffe Strategy Group and a frequent contributor to CBC's Power & Politics's power panel — former Liberal staffer Dave Gene, executive assistant to the Provincial Building and Construction Trades Council of Ontario Igor Delov, and Peter Kennedy of the Canadian Autoworkers Union are all listed as directors on the group's corporate records.

The group formed in late 2014.

While most third-party groups are keeping the exact figure dark, Bernard called the cost of the Raptors buy "substantial."

Political sources have said each 30-second TV ad running during the playoffs could cost tens of thousands of dollars.

"We are funded entirely by donations, large and small, from individuals, organizations, and groups — including labour unions — from coast to coast to coast," said Bernard in an email to CBC.

The Conservative Party is trying already to link Engage Canada to Trudeau's Liberals.

"The Raptors lost last night, but at the end of the game, the prime minister was smiling from ear to ear. That's because anti-Conservative attack ads were in prime spots during the game and the Liberal Party didn't have to spend a cent because a special interest group called Engage Canada did their dirty work for them," said Conservative MP Mark Strahl in the House Tuesday.

The Conservatives lately have been attacking the Liberals' plan to include Unifor on a panel meant to advise the government on the make-up of an independent body that will decide how to dole out almost $600 million over the next five years in tax credits and other incentives for news organizations.

Spending spree coming to an end

Political advertisers can take advantage of a federal election spending carte blanche period for the rest of the NBA playoffs, but that spree comes to an end June 30 when the "pre-writ" period begins.

Once the pre-writ period starts, registered third-parties can spend up to $1,023,400 nationally — and just half of that ($511,700) once the official election campaign period begins.

"This is the first time we're going to have a regulated pre-writ period for political and partisan advertising. So this is the first time that Canada has made this step to regulate political advertising ahead of the actual election call itself. So I think this is a really important step to see how that goes," said Democratic Institutions Minister Karina Gould before a cabinet meeting in Ottawa Tuesday morning.

"Of course, following the election, we'll look forward to hearing expert advice as to whether, you know, this is the right approach."

The pre-writ period also introduces new registration rules. Any third party that spends more than $10,000 or gets donations that total more than $10,000 in the pre-election period must submit interim reports to Elections Canada with more information.

Meanwhile, audiences are likely to see more such ads before the month is out.

"We know that we can spend a fair amount of money from now 'til the end of June and that's exactly what we intend on doing," said Dias.

Bernard told the Canadian Press that Engage has plans to run ads up to the end of June, and will "see what happens" after that.

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