The CBC Pollcast, hosted by CBC poll analyst Éric Grenier, explores the world of electoral politics, political polls and the trends they reveal.

On Monday night, Donald Trump and Hillary Clinton will take part in the first presidential debate. The confrontation comes at a time when the polls are showing a tightening race.

And depending on who uses the platform best, the debate could set the tone for the remaining 46 days of this unpredictable campaign.

The debate will be held on Monday night at Hofstra University in Hempstead, New York. Hosted by the NBC's Lester Holt, the 90-minute affair will tackle three topics: America's Direction, Achieving Prosperity, and Securing America.

What do Hillary Clinton and Donald Trump need to do to come out of the debate in a stronger position than when they went in? What pitfalls and traps do they need to avoid?

And what impact will the absence of the Libertarians' Gary Johnson and the Greens' Jill Stein, who combined have over 10 per cent support in the polls, have on their numbers, and the narrow gap separating Trump from Clinton?

To help set up the debate, Keith Boag, the CBC's senior reporter in Washington, D.C., joins Pollcast host Éric Grenier.

Listen to the full discussion above — or subscribe to the CBC Pollcast and listen to past episodes.

Follow Éric Grenier and Keith Boag on Twitter.