It's not Chretien's fault; he was too busy uniting the whole country against Quebec Separatists and Alberta Firsters. But--and you know I have the little red LPoC card now and am seriously thinking of emailing them another fiver to support their efforts--if you look at Canadian history (esp. provincially) you see that the most common way in which parties "unite" is that one party's vote collapses and goes en masse to the other and all the infrastructure and support groups and organization that the first party has built up over the decades disintegrate and Zalmoids become B.C. Libs, and P.C.s become CPoCs, for example, and so on and so forth.
If I were Mr. Mulcair and looking at a poll like this, that's the result I would be gunning for.