The Globe and Mail predicts a 79% probability of the Tories winning the most seats, probably a minority government. The NDP is at 21% and the Liberals at 0%. They predict the NDP and Liberals have a 95% chance of winning a majority of the seats together.
That's similar to what happened in the UK. The Tories were projected to win a minority but Cameron won a majority. My guess is that Harper is making a bet he will pull off a similar victory.