This morning they and Canadians everywhere will have the answer. Many last night were predicting a close vote. If that is what happens, little will be clarified. A No result, if it is slim, will not resolve the issue of Quebec's status within Canada. A narrow Yes will open months of bickering over how exactly Quebec should be allowed to break away and when.
All the while, the rest of Canada and much of the world are asking Quebeckers a different question: "Pourquoi?". Why are you so agonised about being a part of the country that three years ago was identified by the United Nations as being the most "liveable in" on the planet? What drives so many of you to want to take the gamble of going it alone?
Figuring that puzzle was easier 15 years ago, when Quebec held its first referendum on separation, with the late Rene Levesque leading the secessionists. Quebeckers had reason to complain that French-speakers were still widely considered second-class citizens in Canada and to worry that their culture and language were threatened by anglophone domination.
Few Quebeckers argue the same today, however. A survey in the francophone weekly magazine L'Actualite earlier this month found that only 4 per cent of voters in the province believed that francophone society was under siege and only a slightly higher number thought the French language might disappear from Canada.
Among those who were planning to vote Yes to separation, 36 per cent cited the need for Quebec to wrest from Ottawa the political power to determine its own economic and political fate, while 28 per cent expressed a weariness with constitutional wranglesand a feeling that breaking away was the only remaining viable solution.
Whether or not they believe it is threatened with assimilation, most Quebeckers are clear that they live in a culture that is different from the rest of Canada's. Seeing that does not need scientific surveys. It is more than language that sets Quebec apart (80 per cent of Quebeckers are primarily francophone).
Visiting Quebec from outside is like stepping into provincial France 20 years ago. There is a grittiness you will not find elsewhere in North America. People smoke more. There are bistros and chip shops that offer hot dogs, frites and "petits liqueurs".
Among a small knot of people who stopped on a pavement in Montreal to witness an outside broadcast by a national radio station, Stephane Lahoud, 24, said it was neither economic issues nor fear of cultural erosion that was driving him to vote yes. For him, Quebec is just different from anywhere else in Canada and that is all. It should therefore be a sovereign land. And the main difference, he contended, is one of political and social values. "The anglophones are just more to the right than we are. We have a system where if someone is sick and needs to go to the hospital, we help them. In the West, you get treatment if you can pay for it. If you can't too bad."
The last 15 years, during which there have been three aborted attempts to amend the Canadian constitution in Quebec's favour, have also left many in Quebec resentful and bitter. Jean Hoffman, 34, an international lawyer, remembers that in 1980, the then Prime Minister, Pierre Trudeau, promised to reward a No vote in Quebec - which he won - with early constitutional reforms. It did not happen. Now, Jean Chretien, Canada's present leader, is making the same pledge. "I don't believe him," Mr Hoffman admits.
Still, Mr Hoffman admitted to being undecided. He had been moved, he said, by last week's demonstration by hundreds of thousands of Canadians in Montreal pleading for Quebec to stay in the federation. "I just hope that all those people who came will remind Mr Chretien and make him keep his word".