Conservative Leader Stephen Harper posted a photo of his children, Ben and Rachel, noting that parents of teenage children already have plenty of debate experience. Unlike during past campaigns, Harper's children have been appearing regularly with their father this time around. Ben is currently in university and Rachel is in high school.
Liberal Leader Justin Trudeau tweeted a video of himself during a boxing photo-op in Toronto on Thursday.
"I thought I'd make one of those jogging politician videos, thing is, I don't jog that much," Trudeau says, referring to a common campaign ad approach, one recently used by Ontario Premier Kathleen Wynne.
"On a big day, this is more my speed."
Trudeau also took a swipe at Tom Mulcair.
NDP Leader Tom Mulcair posted a series of tweets aimed at presenting himself as the alternative to Harper and his "failed record."
Green Party Leader Elizabeth May stuck mostly to retweets on a variety of topics as the debate approached.
All the leaders' tweets stirred up lots of discussion online.
Many liked Harper's picture.
Others commented that the Tory leader was trying to appear more human.
Many agreed that debating teens is tough.
Some were puzzled by Trudeau's tweet.
Some compared it favourably to Harper's recent Twitter video about Netflix.
And, predictably, there were lots of jokes.
There were more than a few confused tweets about Mulcair posting in the third person.
But others were digging his message.
What do you think of the leaders' pre-game tweets. Share your thoughts with us on Twitter @CBCnews or in the comments below.