Voters go to the polls on Monday in the federal riding of Toronto-St. Paul's in a byelection some perceive as a referendum on Prime Minister Justin Trudeau and the Liberal government...

Many pollsters and pundits say a Conservative victory will put pressure on Trudeau to step down as Liberal leader. Even a Conservative loss — if marginal — could be problematic for him.

"If we do end up on Monday night with a two, three, four, five-point win for the Liberals, the Liberals will be happy to have a win, but that still means that the country is going toward a big majority government for [Conservative Leader] Pierre Poilievre," polls analyst Éric Grenier, who runs thewrit.ca, said in an interview on Rosemary Barton Live.