His debut ended with one injury, two arrests, and a lot of heckling.
The unusual scene Thursday was certainly not the one Coderre would have scripted. But it achieved a feat he has pursued, and attained repeatedly, in a colourful political career: lots of media coverage.
The longtime federal politician dealt with booing protesters who sought to sabotage the event where he announced he's leaving Ottawa for a Montreal mayoral bid.
The campaign launch had been planned for months. Coderre chose the picturesque square in front of city hall to declare his candidacy for the November election.
But the backdrop wouldn't co-operate.
Behind him stood a couple of dozen protesters, some of whom held up signs demanding more social housing. The demonstrators jeered Coderre and clanged pots as he walked to the podium and again when he announced his plan to run for mayor.
A couple of them, wearing sunglasses and bandanas over their faces, loomed right behind Coderre as he spoke to the crowd.
One journalist asked Coderre for his position on a controversial municipal bylaw that, among other things, makes it illegal for protesters to cover their faces. The bylaw has drawn the ire of demonstrators since last year's student strikes.
As Coderre started to answer the question, one of the demonstrators cut him off by shouting: "You don't have any political courage, Mr. Coderre."
The political veteran saw an opening and swept in.
"Those who demonstrate wearing masks... do not represent Montrealers as a group — and I will respect everybody," he said defiantly, drawing a shower of jeers from the nearby protesters. Coderre said he supported the bylaw.
"Is that clear?"
One of the masked protesters confronted Coderre even before he reached the podium. The former immigration minister responded by reaching out and pulling the black bandana from the man's face.
Following the event, those two masked men who'd been part of Coderre's unofficial, unwanted campaign backdrop were arrested by police.
Things became especially heated during one of the arrests. An elderly demonstrator was injured after being pushed to the ground during a scuffle with police.
The man was brought to hospital in an ambulance. Police later said the injury was not life-threatening.
Before Thursday, Coderre's aspirations for the mayoralty of Canada's second-largest city were a poorly kept secret.
He publicly toyed with the idea of either running for the federal Liberal leadership or for the mayor's office in Montreal. He eventually declined to run for the Liberal leadership, a contest won handily by Justin Trudeau.
Coderre made the initial announcement earlier Thursday through a video on social media.
The outspoken MP has cultivated a huge online following by sharing his thoughts on a variety of issues — such as offering running commentary on Montreal Canadiens hockey games.
During the news conference, he was also asked whether he's the right person to take the helm in Montreal, a city that has been consumed by corruption and collusion.
"I have nothing to hide," said Coderre, whose name surfaced during the inquiry into the federal sponsorship scandal involving the Liberal party. "I was not even blamed in the Gomery report, so I have nothing to do with it."
He added that he was not in charge of awarding contracts while he oversaw the federal portfolios of immigration and sports.
Coderre was touched briefly by the sponsorship scandal, when it was revealed he'd stayed at the cottage of an advertising executive.
"Old stories like this will surface, but you know what? There's been three elections since then and I believe in the confidence and the judgment of people who gave me their support," Coderre said.
He announced that on June 2 he will step down as MP in the Montreal riding he has represented for 16 years since winning it in the June 2, 1997 federal election.
In Ottawa, Coderre has a reputation as a populist, backslapping politician who has frequently sought the media spotlight — and found it.
Coderre made headlines over the years for travelling to Afghanistan on his own to see Canadian troops; publicly feuding with NHL star Shane Doan over what was rumoured to have been an on-ice slur against a francophone referee; and quitting as the Liberals' Quebec lieutenant in a huff.
Even as a boy, Coderre delivered fodder for the news cameras.
A chatty, 15-year-old Coderre explained to a TV interviewer from the French-language CBC how he had spotted a UFO.
"One night I was in the middle of making observations and an object appeared and floated in the air," said the young Coderre, a self-described amateur astronomer at the time.
"At first, I thought it was an airplane."
Coderre, who spent a few years as a radio announcer before entering the House of Commons, held several cabinet posts in the Chretien and Martin governments.
The 49-year-old father of two expressed pride Thursday in his Ottawa track record. He claimed credit for bringing the World Anti-Doping Agency to Montreal when he was sports minister in the 1990s.
Some fellow Liberals have privately complained over the years that Coderre was more interested in promoting himself than his party.
While in the Chretien cabinet, Coderre was seen as a rival of fellow minister Martin Cauchon. Both men were considered future leadership candidates.
But Cauchon now says he believes Coderre would make a good mayor because he's perceived as being close to the people.
"He's going to walk the talk, he's going to be a mayor of action and he's going to shake the apple tree," Cauchon, a former Montreal MP, said in an interview.
"He's going to promote the city, he's going to be a proud mayor... Chances are that Montreal will move forward with him a bit more than with anybody else."
Coderre may even have scored some political points in the tumult of Thursday's launch.
Shortly after the event, a prominent Montreal newspaper columnist gave Coderre credit for how he handled the noisy protesters.
"Coderre did not lose his cool and even delivered his message," Yves Boisvert, who acknowledged he is not a fan of Coderre's, wrote in a blog post on the La Presse website.
"I think that he had guts."
Polls suggested Coderre is the early front-runner, with a big lead, although the race could be tossed into uncertainty by any number of variables.
One such variable is whether the current interim mayor will break his promise not to run. Michael Applebaum was elected by city council to serve as mayor after Gerald Tremblay stepped down last fall amid corruption allegations.
So far, Coderre's opponents include veteran mayoral hopefuls Louise Harel and Richard Bergeron — two candidates who have struggled in past attempts to win over Montreal voters.
The campaign attacks have begun.
A member of one rival party reportedly reserved several Internet domain names that carry variations of his name "Team Coderre," in order to portray him as amateurish and unprepared.
Harel said Thursday that she thought Coderre's campaign launch lacked fresh ideas and she questioned what he could accomplish for Montrealers.
"I've followed him (on social media) for more than a year — he's a very good hockey analyst," she said.
"But I haven't heard him talk about Montreal in any way... (even) as Montreal went through its most difficult period in its history."
Harel acknowledged, however, that Coderre's personality could add some colour to the five-and-a-half-month election campaign.
"It's true that he's entertaining. But we don't need a mascot in Montreal. We don't a need a mascot as our mayor."
-With files from Pierre Chauvin and Joan Bryden in Ottawa
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