Election 2015 polling: political science prof takes a deeper look at what the data reveals

Media coverage of election polling is usually limited to the “horse race” aspect during the campaign but a deeper look at the data by a U of T political scientist provides a more revealing analysis. 

The Forum Research polls published in the Toronto Star note that the raw polling results are housed at the U of T political science department. U of T News interviewed Associate Professor Christopher Cochrane of political science and alumnus Lorne Bozinoff, president of Forum Research, to get their views on the data. 

The Aug. 10 poll showed that 34 per cent of Canadians would vote for the NDP; 28 per cent for the Conservatives and 27 per cent for the Liberals. Four per cent would vote for the Green party and 6 per cent for the Bloc Quebecois. U of T News sent Cochrane the 17-page background report that came with the poll. 


“I think there is a lot to the main inference that the NDP surge in the polls wasn’t just a flash in the pan or a rogue poll, but rather a sustained pattern of increasing support for the party. Whether they can maintain or build on this support throughout the campaign is a question that nobody can answer at this point. Indeed, these poll results are mixed for all parties. 

First, there is reason to be skeptical that the NDP are in fact in the lead. Different polling companies are reporting different results. The Conservatives are in the lead, for example, in a Postmedia poll for the National Post.  There is also the possibility that Conservative support is underestimated in the polls. We’ve seen incumbent support underestimated in the past two elections in Alberta, and also in the last election in BC. Conservative support was consistently underestimated in the polls going into the last federal election. NDP support was over-estimated.

There are different explanations for this, ranging from a pro-incumbent bias of undecideds to poor sampling coverage of right-leaning voters in opinion polls. It is difficult to say. I note, however, that 34 per cent of the respondents to this poll claim to have voted for the NDP in the last federal election, compared to just 28 per cent who claimed to have voted for the Conservatives. This underestimates Conservative support in the last election by 12 points. In any case, we should be leery about these kinds of recall questions, given that people may have forgotten how they voted, or they may be embarrassed to admit their real vote.

Second, notice how Conservative supporters are the strongest supporters of their party (70 per cent support their party strongly), compared to 61 per cent of Liberal supporters and 54 per cent of NDP supporters. NDP support is especially soft. This could mean a few things, but one thing the Liberals and NDP need to worry about is some of these soft supporters not bothering to vote.

If Conservative supporters are underestimated in this poll (as I suspect they are), and if Conservative supporters are more committed (as this poll suggests), then it is not hard to imagine the Conservatives creeping back into majority government territory, which would be a (short-term) disaster for the Liberals and NDP. That said, there are plenty of reasons for the Conservatives to be worried. In the National Post poll they asked respondents for their second-favourite party. The Conservative party was very rarely chosen as second choice (11 per cent), and nearly three times as many chose either the NDP or the Liberals. 

Given the greater flexibility of NDP and Liberal supporters, the pattern of second-choices leaves open the possibility of an anti-Conservative surge in the direction of either the Liberal or NDP parties, which would almost certainly defeat the Conservatives. 

Third, in terms of issue ownership, Mulcair does especially well on the environment (and Harper poorly) and Harper does especially well on national security. It is interesting that Harper does not enjoy an advantage on the economy and that Trudeau does not enjoy an advantage on any of these issues (though I suspect he’d do especially well on national unity, for example). The Conservative pitch on the economy doesn’t seem to be strong enough, according to this poll, to assuage people’s concerns about poor economic prospects. A bad economy is a difficult hurdle for incumbents to overcome.” 


Bozinoff noted that unlike the two other main parties, the NDP does not have a “gender gap” with 33 per cent of men and 34 per cent of women saying they would vote for the party. 

Only 23 per cent of women said they would vote Conservative compared to 33 per cent of men; for the Liberals, 31 per cent of women said they would vote for the party with 24 per cent of men saying they would vote Liberal.

A new Forum Research poll released (but not covered by major news outlets) on Aug. 17 shows the Conservatives in the lead in Ontario.

“Ontario is where federal elections are won, especially with the new seat allocation. Usually, the Liberals and the Conservatives trade first place in the province, or achieve uneasy parity,” Bozinoff said.

“Now, however, the Liberals are shut out and it is the NDP the Conservatives must contend with. With Ontario in the government column, the NDP must have a strong presence in the other two battleground provinces, Quebec and BC, to stand a chance of victory.”

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