From what I've read in the media, the Montreal Carabins seem to be heavily favoured over the Mac Marauders in today's Vanier Cup (number 50). A lot of that has to do with beat the heavily favoured Laval Rouge et Or twice this season, including in the Dunsmore Cup to win the Quebec conference.
However last week the Carabins only beat the University of Manitoba Bisons 29 to 26. Manitoba only went 4 and 4 during the regular season in the Canada West, themselves upsetting the Calgary Dinos to win the Hardy Cup. I haven't checked, but I doubt the Bisons were in the top ten at the end of the regular season. Against Montreal, Manitoba actually had 25 first down to the Carabins 21.
Montreal didn't have much of a running game at all, rushing 22 times for a 2.9 average. Mac obviously has a good run defence, so don't expect the Carabins to gain a lot on the ground. Montreal does have a good passing game gaining a massive 421 yards on 24 for 35 passing. This may be way Mac has a chance, as the Mac secondary is arguably one of the best in Canada led by fifth year player Joey Cupido, who has a lot of interceptions in his career. If Mac is going to win, they're going to have to have some picks.
Montreal was also heavily penalized, with 11 infractions for 81 yards versus 4 for 30 for Manitoba.
Montreal gave up 4.3 yards per carry to Manitoba so that's good for Mac's run game.
Of course the X-factor is that the game is in Montreal. If it were in Southern Ontario, I doubt Montreal would be favoured as much as they are.