U.S. President Donald Trump's trade war and annexation threats have upended Canada's election and improved the fortunes of the Liberal Party, which could win a fourth consecutive term in power next week.

By questioning Canada’s sovereignty, President Trump changed the focus of the race from the failings of the Liberal government to himself.

Canada’s Pierre Poilievre seemed to be cruising toward victory in the next election. His Conservative Party was polling around 20 percentage points ahead of Justin Trudeau’s Liberals because of growing voter frustration around political scandals and rising housing costs.