Poll Tracker: 3 polls, 3 leaders, 3-way race

After the polls hinted at strong trends in favour of the Liberals and against the Conservatives, three new surveys published Friday have muddied the waters — suggesting the race may be back to the tight three-way contest that has prevailed for much of the campaign.

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The CBC Poll Tracker is back to suggesting a modest lead for the New Democrats at 32 per cent, followed by the Liberals at 29.8 per cent and the Conservatives at 29.7 per cent. The Greens are averaging 4.4 per cent support, while the Bloc Québécois is down to 13.1 per cent in Quebec.

This marks the first drop for the Liberals in the Poll Tracker since Aug. 24, ending a consistently positive trend for the Liberals that was stretching to three weeks. For the Conservatives, this is their highest standing in the polls in almost a month. All three of the new polls are pointing toward an uptick for the Conservatives:

• EKOS Research, in its poll for iPolitics, had the Tories up 2.3 points (since its previous survey) to 31.8 per cent, putting them ahead of the NDP (29.6 per cent), and the Liberals (26.9 per cent). The Liberals and NDP were both down, but marginally so.
• Nanos Research, in its daily tracking for CTV and the Globe and Mail, had the Conservatives up 4.6 points from its last independent three-day rolling sample to 30.8 per cent, putting the party just behind the Liberals (30.9 per cent) and ahead of the NDP (29.9 per cent). The Liberals saw no change of consequence, while the New Democrats were down almost three points.
• Forum Research, in its latest poll for the Toronto Star, had the Conservatives up four points to 28 per cent, putting them in a close race for second with the Liberals (29 per cent, down three points), but well behind the NDP (36 per cent).

What to make of the discrepancies? They are the product of a three-way race and the margin of error, which ranges from two to three points in these polls. Sampling error, methodological differences and polling dates (which slightly differ across all three of these polls) can explain much of the variation.

Statistically speaking, neither the New Democrats nor the Liberals experienced any shifts in support outside of the margin of error. But it would appear that the NDP continues to be holding steady, while the Liberals may have plateaued or, at worst, come down a little from their recent surge. A rebound for the Conservatives seems likely, as two of the three polls had the party increasing outside of the margin of error, and the third had their gain just inside it.

Toss-up in the seat count

If an election were held today, the seat projection model's best guess at the outcome would be 115 seats for the NDP, 113 for the Conservatives, and 109 for the Liberals, with the Greens taking one. That is about as close as it gets.

The likely ranges for the parties paints only a slightly clearer picture, with the NDP at 101 to 132 seats, the Conservatives at 98 to 136 seats, and the Liberals at 86 to 123 seats. This suggests that the NDP has the highest floor, the Conservatives have the highest ceiling, and the Liberals have potentially the least efficient vote. But the three parties still have almost even odds of winning, at least at this stage of the election campaign.

CBC's Poll Tracker aggregates all publicly released polls, weighing them by sample size, date and the polling firm's accuracy record. Upper and lower ranges are based on how polls have performed in other recent elections. The seat projection model makes individual projections for all ridings in the country, based on regional shifts in support since the 2011 election and taking into account other factors such as incumbency. The projections are subject to the margins of error of the opinion polls included in the model, as well as the unpredictable nature of politics at the riding level. The polls included in the model vary in size, date and method, and have not been individually verified by the CBC. You can read the full methodology here.

The questions asked in the polls mentioned in this article were as follows:

Nanos: "If a federal election were held today, could you please rank your top two current local voting preferences?"

Forum: "If a federal election were held today, which party are you most likely to vote for?"

EKOS: "If the federal election were tomorrow, which party would you vote for?"