In a tight Canadian election that will be remembered for Prime Minister Justin Trudeau’s self-inflicted wounds, one thing that seems clear is that neither of the two main parties is poised to win enough seats to form a majority government. Trudeau, leader of the Liberal Party, would have to join forces with the Green Party or the left-leaning New Democrats to stay in power for a second term. If the opposition Conservatives can muster the most seats by a good margin, their leader, Andrew Scheer, could cozy up to the Quebec separatists to form a government. The horse trading would start in earnest after the Oct. 21 vote.

1. Why is Trudeau wounded?

Re-election was supposed to be a cakewalk for him. Yet missteps and an embarrassing revelation from the past have tarnished his credibility and raised doubts about his leadership. The release of photos and a video of him in blackface make-up decades ago undermined his image as a champion of diversity. So did his push to get Canada’s first indigenous attorney-general -- Jody Wilson-Raybould, whom he’d appointed -- to help allow SNC-Lavalin Group Inc. settle a fraud and corruption case out of court. Photos of Trudeau and his family in what many considered over-the-top garb during a trip to India also didn’t help.

2. Was his term a failure?

No. The son of Canada’s most famous prime minister, Trudeau burst onto the scene in 2015, charging from third place in the campaign to win a convincing majority. His “sunny ways” outlook and pledges to fight for the middle class resonated, especially with young voters. And he got stuff done. His government legalized recreational use of marijuana, making good on a campaign promise. He stood up to U.S. President Donald Trump to preserve important parts of the North American Free Trade Agreement in its proposed successor accord. He gets high marks for his economic stewardship, including opening the door to the most immigrants in more than a century. He introduced a nationwide carbon tax in a bid to lower greenhouse gas emissions.

3. Can he still win a second term?

It’s certainly possible, but a late surge by the New Democrats and the separatist Bloc Quebecois has eroded support for Trudeau’s party. A poll tracker compiled by the Canadian Broadcasting Corp. predicts the Liberals will win in 141 districts, ahead of the Conservatives at 134, both still well short of the 170 needed to form a majority. The Bloc is projected to win 33 districts, versus 25 for the NDP. The Liberals and Conservatives are still deadlocked in popular support, each with 32 per cent, numbers through Sunday show.

4. What would a minority government look like?

If no party wins a majority in the 338-seat House of Commons, then Trudeau -- as the incumbent -- would likely be given the first crack at forming some sort of coalition. The New Democrats are the most obvious partner for Trudeau, though such a tie-up would make oil and gas development more problematic. The NDP is opposed to the expansion of the Trans Mountain oil pipeline, which the Trudeau government bought last year for $4.5 billion after Kinder Morgan Inc. walked away. The Greens are another potential dance partner for Trudeau, though they would have to win a handful of seats to make a difference. The CBC poll has them winning in four districts. It’s shaping up to be political gridlock as the parties try to come to terms on some form of alliance.

5. What if Trudeau fails?

If Scheer wins enough districts to be close to a majority, he could turn to the separatist Bloc Quebecois for support. While he’d never surrender sovereignty to the Bloc, he could offer some increased powers or revenue for the French-speaking province. One problem for that potential alliance is Canada’s response to global warming. Scheer has pledged to scrap Trudeau’s carbon tax, while the Bloc has made fighting climate change one of the cornerstones of its platform.

6. How have minority governments fared in Canada?

Minority governments have ruled Canada about 25 per cent of the time since 1963, lasting on average less than two years, or half the standard four-year term. The most recent minority was led by Conservative Prime Minister Stephen Harper from 2008 to 2011. (Trudeau’s father, Pierre, led a minority in the 1970s.) Minorities can be good for investors. Since 1935, Canadian stocks have returned on average 12 per cent in the 12 months after the election of a minority government, compared with 8% in the year following a majority victory, according to research by Brian Belski at BMO Capital Markets.

--With assistance from Chris Fournier.