Based on the results of the 2008 election, a coalition running on a joint platform and a common slate of candidates could add 42 seats to the current NDP-Liberal total of 114 MPs, bringing it on the winning side of a governing majority.
The bulk of those gains would be Liberal ones and more than half of them would be registered in Central Canada.
In Ontario, a combination of the 2008 NDP and Liberal vote would result in the election of 15 more Liberal MPs.
In Quebec, such an arrangement would translate into nine more Liberal seats — almost doubling the party’s score in that province.
Under such an arrangement, the NDP would add only a handful of new seats to its take, mostly in Western Canada.
One further fact to consider: in 2008 we had a turnout of only 59.1% of voters, compared to 64.9% in 2006 and 60.9% in 2004. If a cooperative agreement with a non-compete element was entered into, I believe that the synergy resulting from the re-energized grouping would attract more disillusioned voters to vote, easily pushing the total participation rate in the next election up to the mid-60's or even higher, with most of the increase going to the new grouping.
This would give the new grouping a substantial majority of votes and hence seats over the Tories, and catapult the LPC+NDP into government. If one considers the results of the 2008 election, it is possible (if the LPC and NDP support held) for a cooperation agreement with a non-compete undertaking between these two parties to result in an absolute majority of seats for the working partnership: