Wednesday, June 2, 2010

Forget percentages - what about real votes?

As this blog concentrates on polls, we're always dealing with percentages. Sure, the parties that receive the highest percentage of votes cast wins, but it is those real votes that decide elections. And, they are probably the best barometer of a party's political support over the years.

Case in point. The Conservatives had 37.7% support in the 2008 election, an increase from their 36.3% result in 2006. That would seem to indicate that the Tories had more support in 2008 than they did in 2006.

But in reality, the Conservatives lost about 165,000 votes between 2006 and 2008, a reduction of 3.1%. In fact, all of the parties except the Greens lost actual, flesh and blood support between the 2006 and 2008 elections.

This chart shows the amount of actual votes each party received over the last three elections. As you can see, both the Conservatives and New Democrats saw gains between 2004 and 2006 but losses in 2008. The Liberals and Bloc Québécois lost votes in each election, while the Greens were the only party to show steady growth in the face of ever lower turnout.From 2004 to 2006, the Conservatives found 1.4 million new supporters. Although we can't know exactly how voters shifted from party to party, it appears that about 1/3 of them came from the Liberals, who lost about 500,000 votes. The New Democrats gained about 460,000 new voters, and the Greens about 80,000. The Bloc lost about 130,000 voters.

Those who gained also brought new voters to the fold, as the number of voters grew by 1.2 million between 2004 and 2006. Perhaps the thought of replacing the Liberal government brought people out of their homes on voting day.

However, about 1 million voters who voted in 2006 stayed home in 2008. This caused losses of 165,000 voters for the Conservatives, 845,000 voters for the Liberals, 75,000 for the NDP, and 175,000 for the Bloc. The Greens gained 275,000 new voters. The loss of support for the traditional parties is not completely due to the drop in turnout. Many of those voters actually went to the Greens.

The following chart shows how the growth or decline in support of each party compares to how their support should have changed due to the growth of the electorate.

For example, the Conservatives had 4 million voters in 2004. Based on the growth in the size of the electorate, the Conservatives should have had 4.1 million votes in 2006 if their growth was proportional to the growth in the electorate. Instead, they had 5.4 million votes. Based on the growth in the electorate from 2006 to 2008, the Conservatives should have had 5.5 million votes in 2008. Instead, they had 5.2 million. This demonstrates how the party's growth between 2004 and 2006 was due to voters changing their allegiance, rather than mere population increase. But their fall in 2008 was due to voters leaving the party.For the Liberals, it is easy to see that their drop in support has been far greater than what we could expect. They dropped from 2004 and 2006, and instead of keeping support and going from 4.5 million votes in 2006 to 4.6 million in 2008, they fell to only 3.6 million.

The NDP has been generally stable, growing more or less at the same rate as the population. However, in 2008 they had 144,000 fewer votes than their 2006 result would have predicted.

This also shows how the Greens have consistently out-performed normal growth, going from 664,000 votes in 2006 to 938,000 in 2008 - rather than the 682,000 normal population increase would have given them.

Getting a good portion of the vote is, of course, important. But being able to get 5.2 million Canadians to vote for you, as the Conservatives did in 2008, requires a bit more work. And when we see the Liberal vote drop from 5.0 million in 2004 to 3.6 in 2008, we can see how difficult of a task they have in front of them.