Teddy here with an interesting analysis based on recent polls and projections. The PQ, it would seem, appears to have lost their natural advantage with voters. The answer as to why, it seems, is actually shockingly simple. Lets compare some polls from Leger Marketing.
An older Leger poll, that has the PQ and PLQ tied at 30%, has the PQ leading among Francophone voters, 37% to 21%, with the ADQ close behind the PLQ at 18%
A recent Leger poll with the PQ at 32%, the PLQ at 31%, and the CAQ at 27% tells the story of what has changed. Francophones are now split 39% for the PQ and 31% for the CAQ, with the PLQ trailing at 18%.
Rather than a 16 point gap among Francophones, who are make up the overwhelming majority in at least 113 of Quebec's 125 ridings, the PQ is now down to a mere 8 point lead over the CAQ.
To fully understand this, you can think of a Quebec Election as two elections going on at once. One in the dozen or so ridings where Anglophones and Allophones have a say, and another in the remaining 113. Polls for all 125 ridings are therefore partly meaningless, because 113 of those ridings will be decided by polls among Francophone voters, and even sweeping all 12 non-Franco ridings does not make up for such a huge gap in Francophone vote intention. The PQ manages to win a majority on a tied vote because the vote is not tied among Francophones.
Now it is, or at least, getting close to being tied. With the CAQ rising, and, doing poorly on the Island of Montreal, all of a sudden those 113 seats are now split in two different groups, the 17 on the Island of Montreal, and the remaining 96. It is those 96 ridings where the PQ has normally managed to turn it's votes into high numbers of seats, but it is those 96 where the CAQ is now challenging, and taking seats away.
One needs to only look to 2007 to see this in action. The PLQ took 33% of the vote and 48 seats; The ADQ, 31% and 41 seats, and the PQ, 28% and 36 seats. The first and third placed parties were within 5% of each other, and, within 12 seats of each other. Had the PQ retained it's natural advantage, the PQ should have been able to win more seats than the ADQ, if not the PLQ as well.
In short; when a 3rd party does well among Francophone voters, the PQ loses it's natural advantage.