Prime Minister Justin Trudeau's popularity was already deflating under the disillusionment that hampers many incumbents, particularly on the idealistic left, before 2 controversies that seemed almost unimaginable given his high-principled public image: first an ethics breach and now a racism scandal.Driving the news: Since a 2001 photo of Trudeau in brownface at an Arabian Nights party was published Wednesday by TIME magazine, 2 prior instances in which he wore blackface have come to light. Speaking today, Trudeau apologized repeatedly but admitted, when pressed, that he was "wary of being definitive" about whether other images might surface.The big picture: Trudeau’s Liberals had been neck and neck with the Conservatives ahead of the Oct. 21 election.“But the Liberals were running a very specific campaign,” says Darrell Bricker, CEO of Ipsos Public Affairs. They “demonized" Conservative candidates by surfacing past indiscretions as evidence the Conservatives were "intolerant and out of touch with where Canada is going.”The blackface scandal "takes this well-crafted weapon the Liberals had created over a long period of time out of their hands," Bricker says."They've also opened up the opportunity for the New Democrats," he adds. That party's leader, Jagmeet Singh, is a turban-wearing Sikh who has spoken passionately about the difficulties facing minority communities.As for Trudeau, Bricker says, "Part of his appeal was his international rock star status. When you expose those pictures to people in the United States, to political leaders, how do they feel?"What to watch: If 1–2% of Liberal-leaning voters in swing districts switch to the left-wing New Democrats that could tilt the election toward the Conservatives. So could low turnout. Trudeau won in 2015 by bringing in new voters, many of whom were young or from minority backgrounds.