Returning to the theme of my pre-election entry, did the Liberal majority of seats result from the “median voter’s” swing (Downsian competition) or from strategic desertion of the third party (Duvergerian tendencies)? Of course, it can be both.
There was clearly a late swing from the NDP to the Liberals–maybe a little more than a couple of percentage points. This looks like strategic voting, not wanting to waste the vote, ensuring defeat of the incumbent by voting for the less-preferred challenger. In other words, Duverger. In fact, this process had been going on for a while, with the NDP slide and Liberal rise being quite correlated in the CBC poll tracker. Yet for most of the final two weeks or so, it seems as if the Liberals might have gaining mostly at the expense of the Conservatives. That still looks Downsian to me: the swinging of votes from incumbent to the more “centrist” challenger. I will leave it to others to define where the median voter lies in Canada, but it seems that he or she prefers a red hue (red being the color of the Liberal party).
One way in which the outcome is not Duvergerian is in the Liberals’ success in Quebec. The party won many more seats there than expected. In fact, it won 40 of the 78 seats in Quebec (51.3%). I have not located a provincial level voting breakdown (anyone?), but on CBC last night it was reported at around 35%. It was further reported that several ridings (districts) were won in the province with just over 30% of the votes. That is not especially “Duvergerian”.
Of course, the presence of a third nationwide party with around 20% of the votes and 13% of the seats is also somewhat of a challenge to Duverger’s Law. This is one of the better showings for a third party in Canada in recent decades.
It is also noteworthy that the mean district-level effective number of parties, by votes, was around 2.7 in this election, hardly changed from 2011, although with more dispersion around that mean (thanks to Ko Maeda, personal communication, for the stats).
A few basic facts about the national level result…
The advantage ratio (percent seats over percent votes) for the Liberals was 1.38. That is very close to the mean (1.35) and median (1.33) of a dataset of 210 FPTP elections I assembled and have done comparative work with.
The size of the the third party, as a percentage of all seats, is at about the 90th percentile. The third party’s vote share is somewhere between the 75th and 90th percentile.
The effective number of parties by votes is 3.33; by seat-winning parties it is 2.50. The figure for votes is well above the mean for FPTP parliamentary systems, which is 2.76; the mean for seats is 2.15. In both of these indicators, this election is again between the 75th and 90th percentiles.
It seems from these figures that Canada still offers a fairly objective case for the adoption of proportional representation: its party system is more multiparty than what is typical for FPTP electoral systems. Whether this election makes such a change more, or less, likely is unclear. On the one hand, majority parties aren’t often known for their enthusiasm about PR. On the other hand, the Liberals were just elected with a manifesto commitment to electoral reform, although not specifically PR.