While both the NDP and Liberals have put a halt to talks of merger, discussion of "uniting the left" is likely to continue among pundits and many party members. The concern is vote-splitting on the left which benefits Conservatives. For instance, in many ridings in the "905" region of suburban Toronto, it seems the NDP's "orange wave" helped Conservative candidates win.

There are reasons both Liberals and New Democrats would benefit from a merger. The NDP, assuming it can hold onto its Quebec gains, needs to expand support to areas that do not traditionally vote NDP, for example the suburban "905" where the party still, in most cases, placed third.

By contrast, the Liberals have a proven track record in many of these ridings (even if they were defeated in many of these places in 2011) in particular in places like Brampton and Mississauga where there are large populations of immigrants and visible minorities.

According to early findings from the Canadian Election Study, Conservative gains among immigrant voters have been overstated, and only Liberals registered positive on the "immigrant vote gap." That is, when the percentage of votes from non-immigrants was subtracted from the percentage from immigrants, only Liberals scored positive with the NDP and Conservatives scoring negative.

In the 1990s and early 2000s, the Reform Alliance had difficulty winning seats east of Manitoba, hence the merger with the Progressive Conservatives which was as much, if not more, about gaining legitimacy east of the Manitoba border as it was about vote-splitting.

For Liberals, combining their strength among visible minorities and immigrants -- and their strength in many suburban regions -- with the NDP could potentially mean an easier path to power for both parties.

However, there are reasons the Liberals and NDP would not want to merge. The NDP are hoping to completely displace the Liberals, crush them in 2015 and take their place as Canada's centre-left alternative.

Meanwhile the Liberals are hoping for a comeback; something that seems a possibility given that the NDP's Quebec gains came by appealing to nationalist voters. For Layton, it will be tough to satisfy Quebec nationalists while not alienating the rest of the country.

On policy, the differences between Liberals and New Democrats are less than what they were in the days of the NDP's predecessor, the CCF. Under Pearson and Trudeau the Liberals came to embrace the welfare state and socialized medicine; meanwhile the NDP in the 1990s and 2000s has moved to the centre, influenced by centrist third way ideas. However, there is an opening gulf between the two parties on national unity, on the Clarity Act, and the threshold for Quebec separation, as the NDP try to maintain the support of Quebec nationalists.

What's problematic is that a merger would reduce our political choices. One of Canada's strengths vis a vis the United States is that we have multiple parties, we are not forced to choose between two monolithic blocks. New parties bring new ideas, invigorating public debate.

However, there is the issue of vote-splitting.

The best solution may be for all three progressive parties -- the NDP, the Greens, and the Liberals -- to vigorously take up the cause of electoral reform. The NDP and Greens already support proportional representation; it is time for the Liberals to come on board. Through a system of proportional representation, the parties can maintain their autonomy and identity without splitting the vote.

Though Harper would not enact such a policy, he benefits from the current first-past-the-post system which favours a united right over a divided left. However, if the NDP, Greens, and Liberals can aim for at least a minority government situation in the next election, they could collectively have the clout to force electoral reform onto the Parliamentary agenda. In the meantime, between now and the next election, all three parties can vigorously promote proportional representation, and try to win the public over.

It is important, however, to urge some caution: electoral reform should not be considered solely a left-right issue, but be considered an issue of fairness. When there was a divided right, many in the Canadian Alliance were sympathetic to the cause of electoral reform. For many Red Tories the Conservative Party is too right wing; for many old-school Reformers, the party is not right wing enough.

Proportional representation, with multiple parties, would allow better representation of the diverse strands of conservatism.

Electoral reform is about fairness, about promoting choice, and preventing the necessity of merging parties into monolithic blocks to avoid vote-splitting. We need an electoral system that better reflects the will of voters, a system where a party cannot form a majority government with less than 40 per cent electoral support. At the current time, the best starting point of reform would be for the Liberals, NDP, and Greens to become strong advocates on the issue.

Hassan Arif is a columnist with the Telegraph Journal in New Brunswick. He is a PhD candidate in urban sociology at the University of New Brunswick and has a background in law and political science. He can be reached at arif.telegraphjournal@gmail.com. You can follow him on twitter at www.twitter.com/hassannb.

Follow Hassan Arif on Twitter: www.twitter.com/Hassan Arif