In the end, however, it might not prove to be such an interesting race. The riding has been a Liberal stronghold for most of its history, with the party having won 10 of 12 elections. And when the Liberals did win, they tended to take it by double-digit margins. Only in 1988 and in 1993, when the Liberals lost the riding by less than 1,000 votes to the Progressive Conservatives and the Bloc Québécois (respectively), was the riding painted anything but red.
It has certainly helped that the Liberals were represented by Coderre, one of the most visible Quebec MPs the Liberals have. Before 2011, he had never won Bourassa by less than 11 points. The New Democrats did give him a run in that election, pushing him down to 40.9% support (the lowest vote share the Liberals have ever had in the riding), but he nevertheless had an 8.6-point cushion. The New Democrats finished with 32.3% of the vote and the Bloc Québécois with 16.1%.
When the New Democrats were polling well in Quebec last year, Bourassa might have been truly up for grabs. When the Bloc was briefly ahead in the province before Thomas Mulcair became leader, they might have even had a chance. But with the Liberals surging in Quebec and both the NDP and Bloc taking a big hit in support, the riding has to be considered a very safe one for the Liberals.
ThreeHundredEight's by-election forecast model (11 for 11 so far!) considers Bourassa a Strong Liberal riding, and does not expect that the Liberals will lose it. The only wildcard at this point is the identity of the candidates, but by the time the by-election is called perhaps the political landscape in Quebec will have shifted again.
As it stands, however, the Liberals would have to nominate a horrible candidate, and the NDP a stellar one, for this riding to not remain in the Liberal camp. The Bloc shouldn't be a factor, and that is why Daniel Paillé is almost certain not to take a run at the riding. The Conservatives are a complete non-player in Montreal, and the Greens less so (they took 8.8% and 1.6% of the vote, respectively, in 2011).
If Bourassa hadn't had an MP like Coderre, it could have been swept up in the NDP's tidal wave in 2011. All else being equal, his departure would have certainly made this riding a difficult one for the Liberals to hold. But with Liberal support surging so dramatically, it seems unthinkable that the Liberals would not be able to retain this riding in a new by-election. A loss here would be a catastrophic blow to Justin Trudeau.
But perhaps the race is not as much of a slam dunk as the provincial swing would suggest. A poll that went unnoticed was released by Forum Research a little while ago, showing that the Liberals were only experiencing a small bump in support from their 2011 numbers.
Forum surveyed 501 residents of the riding on May 17 by IVR, finding that 89% of respondents were aware of Coderre's decision to resign and run for the mayoralty. The poll gave the Liberals 45% support in a new by-election, followed by the Bloc Québécois at 26%, the NDP at 21%, and the Conservatives and Greens at 3% apiece.
That represents only a four-point gain for the Liberals, while the Bloc was up 10 points and the NDP was down 11. Considering the province-wide support for the Liberals and Bloc, this is counter-intuitive.
A few notes about Forum's sample. The same issue of over-sampling older voters and under-sampling younger voters has occurred here. According to Forum's report, 53% of its sample is 55 or older, instead of the 39% it should be for Bourassa. Only 9% of the sample is under the age of 34, instead of the 26% it should be. Only 41 voters aged 18-34 were sampled, which theoretically has a margin of error of +/- 15.3%. Those 41 voters had to be re-weighted to represent some 130 voters, meaning that small, error-prone sample was more than tripled.
In terms of how respondents said they voted in 2011, the sample seems fine for every party but the NDP. Only 20% of respondents said they voted for the NDP in the last federal election, rather than the 32% who actually did. Was the sample re-weighted to reflect this discrepancy? If not, the poll could potentially be under-representing NDP support (though not enough to overturn the overall prognosis).
The number of francophones and non-francophones sampled seems adequate, however, though of course the issue of other discrepancies in the sample still exist. Nevertheless, voting intentions were little different among francophones, with the Liberals down to 43% and the Bloc up to 28%. Among non-francophones, however, the Liberals were way ahead: 69% to only 12% for the NDP and a smattering of support for the other parties.
The by-election in Bourassa could be called many months from now in the fall or even early winter, so there is plenty of time for things to change. Six months ago, the NDP was leading the Liberals in Quebec by 10 points, rather than trailing by 17 as they do now. Where things will be six months from now is anyone's guess. But unless something dramatic occurs before the by-election is held in Quebec, the riding should be considered the Liberals' to lose.