As part of its challenge to the election results in seven ridings, the Council of Canadians asked Ekos to study the experiences of individuals in those ridings. Ekos surveyed respondents in the seven ridings and then compared those responses to a survey of Canadians residing elsewhere. The full report from Ekos is here.

This study has presented evidence which strongly suggests that in the subject ridings there was a targeted program of voter suppression in place. It was reported to be administered to tens of thousands of electors based on these samples … If these responses were the constructions of disgruntled non-Conservative voters, one cannot explain why the targeting effects were not present in the comparison group.

Exposure to these calls clearly had a dampening effect on the propensity of non-Conservative supporters to vote. Using different methods, we would estimate the effect in the range of 1.2 per cent to 1.8 per cent.