Four leaders will face off tonight in the first televised debate of the federal election campaign.

       The French debate on TVA, one of Quebec’s most-watched networks, comes at the midpoint of the campaign and could prove crucial to the outcome on Sept. 20.

       Only four leaders – the Liberals’ Justin Trudeau, the Conservatives’ Erin O’Toole, the Bloc Quebecois’ Yves-Francois Blanchet and the NDP’s Jagmeet Singh – will take part.

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       The Green party’s Annamie Paul and the Peoples’ party’s Maxime Bernier were not invited to participate.

       The TVA debate was seen as pivotal in the 2019 campaign.

       Then-Conservative leader Andrew Scheer’s evasiveness on the issues of abortion and medical assistance in dying was widely seen as halting early Conservative momentum, ultimately enabling Trudeau’s Liberals to eke out a minority win.

       The performance of Blanchet, a newcomer to federal politics at the time, was also credited with giving new life to the Bloc Quebecois, which helped rob Trudeau of a second majority mandate.

       The TVA debate is in addition to two official debates organized by the Leaders’ Debates Commission. The official debates are scheduled to take place next week – in French on Sept. 8 and in English on Sept. 9.

       Paul will participate in those debates, but Bernier, who didn’t meet the independent commission’s criteria for participation, will not.

       The TVA debate involves a series of face-to-face encounters between two leaders at a time, allowing for sharper and longer exchanges.

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       Tonight’s two-hour debate begins at 8 p.m. ET.

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