Last week, a new poll emerged suggesting that the Liberals had made enormous gains in national voting intentions, coincidentally after Justin Trudeau's announcement that he was running for the leadership of the party. Is this surge in support something that Liberals should expect as the race continues?
The poll by Nanos Research put the Liberals at 30.1 per cent support nationwide, edging out the New Democrats and putting them within the margin of error of the leading Conservatives. Compared to Nanos's previous poll conducted at the beginning of September, this represented a gain of 5.5 points – a big, statistically significant spike for the third-place party.
Other polls will provide a clearer picture as to whether Mr. Trudeau's candidacy has really caused the Liberals to move into contention. If that proves to be the case, that would be a very good sign for the Liberals as this sort of bounce is not typical.
What we can learn from past races
Though the polling data is rather thin, the examples of the 2006 Liberal and 2012 NDP leadership races suggest that no major candidate was able to give his party the sort of boost demonstrated in the Nanos survey. (Read our infographic) In polls taken by the same firms before and after Brian Topp's announcement in mid-September 2011 that he would run for the leadership of the NDP, the party actually suffered a drop of about three points. Thomas Mulcair's announcement, made a month later, also had no positive effect on the national support of the New Democrats: it dropped by about 1.5 points.
In 2006, announcements by Stéphane Dion and Michael Ignatieff at the beginning of April corresponded with an insignificant 0.5-point drop for the Liberals in polls conducted by the same firms before and after, while Bob Rae's announcement at the end of April was greeted with another 0.5-point decrease.
The jump in support for the Liberals in this recent single poll may be an ephemeral thing, but where might the party's fortunes go from here?
The most recently contested NDP and Liberal leadership races tell different stories, in part because the two took place under wildly different circumstances.
The 2012 NDP leadership race
The NDP's leadership campaign was launched under a dark cloud due to the death of Jack Layton, coming so soon after their stunning electoral breakthrough. The New Democrats were polling well throughout the summer and even saw a brief increase in public sympathy after Mr. Layton's passing, but as soon as the leadership race started to roll with the announcement of Mr. Topp's candidacy on Sept. 12, the party's support began to slide.
From an average of 31 per cent in polls taken in September after Mr. Topp's entry into the race, the NDP dropped to 30 per cent in October, 29 per cent in November and December, and finally 28 per cent from January to March, prior to Mr. Mulcair's win. The NDP leadership race, then, was a drain on the party's support.
The 2006 Liberal leadership race
In 2006, the Liberals just were coming off a disappointing electoral defeat. Support for the party averaged 28 per cent, only slightly above the January 2006 electoral result, in April when Mr. Dion and Mr. Ignatieff entered the fray. From there, the party's support held firm at an average of 28 per cent in May before dipping slightly to 27 per cent in June 2006. It then increased to an average of 29 per cent in July and August and by November, on the eve of the leadership convention, the Liberals were averaging 31 per cent in national voting intentions, putting them in range of the Tories. The last contested Liberal leadership race, in contrast to the NDP's, resulted in an increase in party support.
On the face of it, that would seem to bode well for Mr. Trudeau and the Liberals. But the subsequent performance of both the NDP and the Liberals after their respective leadership conventions should encourage caution.
When the leader's picked
Stéphane Dion's victory on Dec. 2, 2006 was followed with a surge in Liberal support – the party averaged 36 per cent in polls taken during the rest of that month. But the party quickly fell back down to Earth, dropping to 34 per cent in January 2007 before sinking to 30 per cent between February and April. By June, six months after the convention, the party was back down to 29 per cent.
The New Democrats also saw a boost in support after their convention. With Mr. Mulcair at the helm, the NDP soared to 35 per cent immediately after his victory and kept that level of support in May and June. The slide began in July, however, as the NDP averaged 33 per cent before dropping to 31 per cent in September. The latest Nanos poll put the NDP at only 28 per cent support, exactly where the party was before Mr. Mulcair was named leader little more than six months ago.
Based on how the polls moved in 2006 and earlier this year, the Liberals might be able to expect a three- to four-point bump in the months after they name their leader in April 2013. But they might also need to expect a drop of two to three points by the end of next year.
This serves as a cautionary tale for the Liberal Party. Mr. Trudeau might give their numbers a boost in the short term and they can probably expect a surge in support after they name their next leader. But this sort of increase can be fleeting, and what matters is where the party's support will be by the time the next election rolls around in 2015. The last three leaders of the Liberals left their parties in worse positions than when they took over, even after leading in the polls for a time. Mr. Trudeau or whoever else wins the leadership will need to break that streak if the party is to survive.
Éric Grenier writes about politics and polls at ThreeHundredEight.com.