I'm Canadian, and lean pretty far to the left. (socially WAY left, financially more to the center.) I was, however, planning on voting Liberal this election as I figured they'd have the best chance of ousting Harper.
Then came C-51, and Trudeau happily went along with it, without so much as a whimper of protest. That, for me, was the moment when I knew I couldn't vote for the Libs. I can't in good conscience give my vote to anyone who cares so little for the privacy of the people they work for, and/or is so weak willed that he'd let something like that pass without screaming and yelling.
So, NDP is getting my vote. I'm a little nervous that they've never had a federal government before, but I trust that Mulcair will do what he says, and more to the point, I trust that he actually respects the Canadian people - something Harper has never done, and Trudeau can't do since he's too busy contorting himself in to pretzels at the behest of his advisers