I'm hearing this question in the blogsphere often: If the Liberals elect a progressive such as Bob Rae or Gerald Kennedy, then how will the NDP differentiate itself? The implied answer to this question is that the NDP will go so far left that it will go into unelectable territory.
I think to do so would be a major mistake for the NDP. The fact is, we should continue to go along a moderate, centre-left course. But you say that the Liberals will do the same thing and sound the same. I think that we can use this to our advantage. We need to point out the fact that the Liberals always sound like they are on the centre-left but always govern from the right. We need to point out that the Liberals have been promising to do progressive things for 13 years and did absolutely nothing to achieve them. Finally, we need to point out the the NDP will work towards implementing progressive policy when it is in government.
The fact is, going further to the left to differentiate ourselves from the Liberals is a BIG mistake. If one wants to go that far left, they can vote for the two Communist parties. And I think that the NDP's position on Afghanistan is a big mistake for the purpose of being moderates of the centre-left.
The Liberals are down for the count right now, and the NDP has an opportunity to take them out. However, we will ruin that chance by going further left. Canada is a nation of moderate voters, after all.