Canada election 2015: What exactly is a 'stump' speech?

Ever feel like politicians just say the same thing over and over again? That's because they do. Each political party crafts a "stump" speech for its leader to deliver when speaking to voters out on the campaign trail. 

Journalists travelling with the leaders can often recite these speeches verbatim because they change so little over the course of an election. Staying on message is a virtue, after all. 

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There are notable exceptions, of course. After Alan Kurdi's body washed up on a Turkish beach last week, Conservative Leader Stephen Harper added a line to his stump speech: "It has shockingly reminded us all of the nature and of the scale of the violence in that part of the world. That is why the Canadian Armed Forces are proudly participating in the fight against the so-called Islamic State." The addition was a response to critics who said his government was not doing enough to deal with the Syrian refugee crisis. 

The other leaders made adjustments as well, but mostly in an effort to deride the Harper government's policies and to promise greater help for refugees. 

But just how important is the stump speech? Why is it so important to say on message? And where does the term "stump" even come from? The CBC's Tom Parry has the answers. Watch the video above.