Elections Canada says an estimated 3.6 million people voted during four days of advance polls running from Friday to Thanksgiving Monday, representing a 71 per cent increase over three days of advance polling in 2011.

The agency estimated that 1.2 million people voted on Thanksgiving Monday, 767,000 on Sunday, 780,000 on Saturday and 850,000 on Friday.

Voters complained of some irregularities with voter information cards, as well as insufficient staff and long lineups.

Some voters who were upset with the niqab debate wore face masks, and in at least one instance a potato sack to vote.

Under Elections Canada rules, electors are allowed to vote while wearing a face covering as long as they take an oath attesting they are eligible and provide two pieces of ID, including one with a current address.

The polls suggest that if an election were held today, it would likely be a toss-up between the Liberals and Conservatives. But with a week to go until election day, there is plenty of time for voting intentions to shift significantly.

Pilot project 'successful'

In an effort to assist voters, Elections Canada launched a pilot project to open temporary offices from Oct. 5 to 8 at select university campuses and community centres across the country.

A total of 70,231 people registered and voted at these locations, the agency said on Tuesday.

"Elections Canada's goal is to ensure that every Canadian who wishes to cast a ballot has an opportunity to do so," said Chief Electoral Officer Marc Mayrand in a written statement.

"I am pleased that our pilot project was so successful and that over 70,000 electors took the opportunity to vote early on select campuses and at select Friendship Centres and YMCAs."

There are approximately 26 million Canadians qualified to vote, Elections Canada says.

The general election is on Monday, Oct. 19.