Actually, I think you'll find it's probably more than 45%. The people who voted in those referenda did so on the grounds they lived in Quebec, right? NOT on the grounds they felt themselves to be Quebecois or whatever. I would have though, especially considering Quebec is still part of Canada, that a significant part of the population of Quebec may not have been born there, not speak French and simply consider themselves Canadian. I think if you took ONLY the people who saw themselves as Quebecois and asked them the independence question the answer would be quite different.
You're right every Quebec citizen voted for the referenda. Nevermind their origins.
However, a few precisions:
The expression "Quebecers" usually applies to every citizen of Quebec. However, there is still a lot of confusion on definition of the word.
Another precision: In English, when they say "Quebecois" this usually refers to the French-speaking portion of Quebec citizens. However this is not a a given. It can also mean citizens of Quebec. For instance, the Conservative federal government passed a motion recognizing that "Quebecois form a nation, within a united Canada". There is still debate as to what "Quebecois" really means in this motion. Is it every citizen, is it the territory of Quebec or is it only the Francophones or everyone identifying with the francophone culture of Quebec? The conservative goverment hasn't been willing to clarify this, as he risks displeasing the hardlines in both camps (ultra-federalists Canadians and ultra-nationalists Quebecers).
Considering these definitions, when I say about 45% (between 40-49% depending on the polls) of Quebecers want to separate from Canada, I refer to the citizens of Quebec, not the Francophones/Quebecois
Now, on the place of French: about 75-80% of the population of Quebec is of francophone descent. About 85% of the population has French as its first language (Francophones + migrants from France, French-Africa, Haïti, etc.). For the other communities, most of them speak French as their second or third language. There aren't much people who can't speak french at all in Quebec (there are some, but not much).
So, as I said between 40-49 % of the citizen of Quebec want independence.
However, if you count only the Francophones (the people who identify as Quebecois first), it's probably closer to 60%.
I'm not sure of the numbers on this, but that is what it used to be last time I heard about such a thing.
The vagueness of the number here is mainly due to the fact that such numbers are rarely published in the medias as it is not really politically correct over here to do these kind of distinction when it comes to sovereignty and the questions of who is a Quebecers or a Quebecois (hence the vagueness of my definitions above).
Such a distinction can be interpreted as a rejection of other ethnic and cultural communities and that is something usually frowned upon.
Jacques Parizeau, Quebec's premier during the last referendum in 1995, said on the night he lost the referendum that the only reason why the independence camp had lost was due to ethnic groups of new migrants and the fact that the NO camp had more money.
People were outraged by the remark and he had to resign. The remark was perceived as a bit racist and as a rejection of migrant communities. These are labels the sovereigntist movement has always tried to avoid at all cost (they always tried to be inclusive despite being mainly composed of Francophones).
Parizeau's remark may have been (remains for many) offensive, but he was still quite close to the truth:
The No camp won over the yes by not much more than 1%. 50,5% for the No and 49,5% for the Yes. This represented about 50 000 people.
It has now been proved that the NO camp didn't respect the election laws and got much more money for its campaign than what it should have had.
It has also been proved a few years ago that many new migrants received their citizenship earlier than expected from Ottawa so that they could vote for the referendum.
Of course, most migrants vote No. Most of them decide to immigrate to Canada, not necessarily Quebec, and many of them don't want any political turmoil of any kind, as it is often one of the reasons they left their country in the first place...
So saying the Yes camp lost because of money and migrants vote is not completely off the mark. Of course, it is only a portion of the truth. Had the Francophones been even more mobilized behind the independance movement, the referendum would have won nonetheless.
I'd like to add that most francophones federalist (who want to remain in Canada) still feel more Quebecois than Canadian. They've got the two identities, Quebecois being slightly more powerful than the Canadian identity...
There are even Quebecois who don't feel Canadian at all, but they still don't want to become independant because they think it'll be a big problem economically. They're afraid for Quebec's economy and its ability to make it out on its own. They think a state of 7,5 millions next to a giant of 300 millions and its henchman of 23 millions wouldn't have much bargaining power... Of course, many prosperous states of around 7 millions exist (Europe has many of them), but none is so close and so isolated like an independant Quebec would be. The plurality of actors in Europe makes it much more easy for small states to promote their interests through alliances with other small or medium states.
Sorry for the numerous digressions.