AFAIK Quebec tends not to elect many Conservatives - probably the fewest per capita in Canada provincially/territorially, per the headline. They elect a lot of Liberal and Bloc candidates. My conjecture (which is irrelevant in days like this when the Libs poll pitifully) is that how many Liberals Quebec (which, like Ontario, has a ton of seats) elects, as opposed to Bloc, has a pretty sizeable indirect effect on who forms governments between the Liberals and Conservatives. I should add that I'm ignorant of where the Bloc is on the political spectrum, so my 'Liberals and Bloc split votes' hypothesis is blind in that respect