A few days ago, Forum Research released the second public opinion poll since the October 2011 Ontario provincial election. It showed the Progressive Conservatives at 41 per cent of overall support, the Liberal Party at 33 per cent, and the NDP at 20 per cent.

These numbers indicate a real shift in public opinion, with the Conservatives regaining the lead they held prior last year’s election campaign. Despite what the numbers show, there are a few reasons why they need to be taken with a grain of salt.

First, this poll was not conducted in the context of an election. Polls conducted outside of an election period offer an interesting look at trends in public opinion, but are not always accurate indicators of how the public would vote during a campaign. This was clear during the last provincial election, when the Conservatives lost the large advantage the polls were showing before the writ dropped.

During an election campaign voters are bombarded with campaign literature, leader’s debates, and political advertisements. They are forced to actively consider their options and make a choice. There is a level of political engagement that doesn’t exist in between elections, and this makes inter-election polling more difficult and abstract.

A second issue with this poll is that it doesn’t take into account the impact of local candidates.  During the last election, Forum Research conducted polls for a number of Ontario ridings without mentioning candidate names. The results were startling: Premier Dalton McGuinty only had a slim lead in his riding of Ottawa South and NDP MPP Cheri Di Novo was trailing Liberal candidate Cortney Pasternak in Parkdale-High Park, traditionally an NDP stronghold. When candidate names were added and a new poll conducted a week later, many of these anomalies were corrected.

This shows how valuable local candidate names are to polling results, and demonstrates another flaw in province-wide polls taken in between elections. With no candidates nominated, polls such as these tend to over-represent momentum and under-represent the impact of candidates.

The poll did show an interesting trend with regard to approval ratings. Despite the Conservatives overall increase in support, leader Tim Hudak’s approval ratings remained low. Mr. Hudak had the lowest approval rating of the three party leaders at 26 per cent, with NDP Leader Andrea Horwath leading at 40 per cent and Premier Dalton McGuinty at 33 per cent. These approval ratings are consistent with what we saw in the election.

While polls will continue to be conducted outside of election campaigns, it is important to recognize their limitations, and proceed cautiously when drawing conclusions from their numbers.

Bryan Bossin is a member of the Toronto public affairs team.