What if we had a FPTP parliamentary system in which there were three national parties, and their vote percentages in any given election were:
We would have to call that fairly typical FPTP stuff. Not your ideal Duvergerian pattern, to be sure, but nothing remarkable in the real world of FPTP elections. Now let’s suppose their seat percentages were:
Pretty unremarkable, too, right?
Yes and no. On the one hand, this is what we should expect with FPTP: the two biggest parties with higher percentages of seats than votes, and the third party with significantly lower seats than votes.
Of the 211 FPTP elections in my database, there are 23 in which the largest party won from 38% to 42% of the vote (regardless of other parties’ percentages and excluding four plurality reversals). Of those 23 elections,* what’s the average seat percentage for the largest party? 54.35%. (The median is 52.63%, and the range is 36.15% to 69.09%.) So a large party winning around 40% of the votes and 54% of the seats is totally unremarkable.
Yet in another sense, the largest party in this Canadian election, the Conservatives, is under-represented–relative to a norm of FPTP expectations. Here I am speaking of the expectation set by the seat-vote equation,** which takes a distribution of the top three parties (plus “others”) and computes a “normal” output of seats for a given voting population and assembly size. Here is what the seat-vote equation thinks the seat distribution should look like, given the actual vote percentages:
We’ll call that 1 “other” seat the Green winner, given that the Greens indeed did win their first elected seat. The seat-vote equation does not do well with regional parties. Fortunately for the equation, the regional party in this election almost disappeared (4 seats for the BQ, down from 50).
So the Liberals did quite a bit better than can be expected for the national third party. As a result, the Conservatives are under-represented, relative to FPTP “norm,” with 18 fewer seats than the equation’s estimate.
For all those who think the Liberals’ run as a viable party is over, be cautious. The British experience tells us that a Liberal party can survive for a good long time between the big parties of left and right. The party’s over-shooting of the seat-vote equation estimate underscores the extent to which it retains an efficient regional distribution on which it could build to win back seats in the future. In percentage terms, it is about where the British Liberal Democrats are in seats. This is a big shift, to be sure, but it is premature to write the party off, or to assume it will merge with the NDP.
Perhaps the bigger question is whether the NDP can survive as a major national left-wing party; first it will have to reconcile its now dominant Quebec wing with the NDP constituencies in the rest of the country. If it can’t, the Liberals will resume relevance, whether or not they surge back to “major party” status again anytime soon.
For all those advocates of proportional representation in Canada, this election is bad news. The first past the post system functioned about as expected, notwithstanding the under-inflation of the governing party’s plurality.
* The elections are: BC 1963, BC 1972, BC 1991, CA 1963, CA 1965, CA 1972, CA 1993, CA 1997, CA 2000 (the last majority government in Canada before this election), MB 1986, MB 1988, NS 1999, NS 2006, ON 1977, QC 1976, SK 1975, UK 1975, UK 1992, UK 2001, IN 1967, IN 1977, IN 1989.
** For details, click the words, seat-vote equation in the “Planted in” line above. There was an entry on election day applying the equation to the EKOS final projection, and many previous entries applying it to various past elections.