When I was a student in Britain and during subsequent visits there I was always fascinated at election time when the BBC’s great journalist Peter  Snow during the election broadcasts would use the Canadian expatriate, the late  Robert Mackenzie who had a distinguished career at the LSE as a Professor of Political Science to analyse the swing factor in the election to predict which seats were likely to fall to the party in ascendancy.

So for example if the swing to Labour were of the order of 5 % they would identify which constituencies based on the last election Labour had come second where the margin of victory  of the Tories was less than 10 % . They then, in a rather impressive ritual, would list these marginal seats and show how many were going to fall to Labour(or vice versa). It was an impressive election spectacle that many viewers enjoyed. Well, we can of course use the same technique in analysing possible election results in Canada by listing all the marginal seats and then calculating the likely result assuming that the swing is consistent and predicting that in the vote shift away from the party that won last time, the vote is highly likely to go to the party that ran second. Of course , this is not always true and some adjustment must be made for new realities and conditions on the ground.

If we adopt this technique in Québec there are some 18 seats where the margin of victory was under 10 %.The Bloc won 11 of them. In 7 of them the second party was the Liberal party. In one of the other Bloc victories the NDP ran second and in the three others the Conservatives came second.

In this election based on the most recent polling the swing appears to be away from the Bloc and toward, so far, the NDP and to a lesser extent the Greens. The Liberal vote is down slightly from last time and the Bloc vote down by as much as 5 % points, and the Conservative vote slightly higher.

So which are these key marginal ridings and what is likely to happen based on these assumptions holding true on election night. Also of course we are aware of the possibility that voters who desert a party may simply stay home and other voters who did not vote last time might  take their place or not which of course can skew the analysis.

Quebec marginals where the Bloc is the incumbent and either Conservatives (C) or Liberals (L) or NDP (N) ran second. The margin of victory in percentage terms is also given.

1. Abitibi- Baie James- Nunavik- Eeyou (C)  9.3 %

2. Ahuntsic      (L)  0.9%

3. Alfred Pellan (L)  9.5 %

4. Brome Missisquoi (L) 2.4%

5. Chicoutimi Le Fjord (C)  6.4 %

6. Gatineau  (N)  3.1 %

7.Jeanne Le Ber (L)  2.6 %

8.Laval (L)  9.7 %

9. Louis Hébert (C) 8.0 %

10. Pontiac (L) 8.5 %

11. Saint Lambert (L)  9.1 %

So the absolute maximum that the Liberals could capture is 7 additional seats plus a long shot in Outremont against the popular New Democrat Thomas Mulcair  where the swing from the Bloc to the NDP would work against them .But if their vote is slightly less and the swing less than 5 % their likely gain might be 3-4 additional seats at best. The NDP seem to be well placed to hold on to Outremont and perhaps win an additional seat in Gatineau. The Conservatives have only 2 additional plausible seats if the swing to them is 5 % points. There are 5 other seats which could be classed as marginals but in 2 of them the Liberals are the incumbent and the Bloc the second party so a switch is less likely in these . In the other three one was won by the independent André Arthur and the Bloc came second. In Brossard La Prairie the Liberals won  by only 0.1 % and the Bloc came second and in Papineau Justin Trudeau the son of former Prime Minister Pierre ElliotTrudeau and Margaret Sinclair won the riding for the Liberals over the Bloc by a margin of 2.8 %. These two are two close to call but I think the Liberals are likely to win in Papineau.