The New Democratic Party of Canada will choose a new party leader at a two-day conference at a Toronto convention centre this weekend, through a process that gives each member a chance to have their say in the future of the party.

With seven candidates vying to be named Jack Layton's successor, the selection process could involve several rounds of voting, backdoor deals between candidates and groups of supporters that shift allegiances and swing momentum from one direction from the next.

Advanced voting is already underway, but many party members will hold out until the leadership convention at the Metro Toronto Convention Centre on March 23 and 24.

The conference will begin with each candidate getting about 20 minutes to address the crowd Friday afternoon, followed by a memorial for Jack Layton that evening.

What follows can only be described as an internal party slugfest, as each candidate and their campaign teams work behind the scenes to sway enough votes in their favour to be named party leader.

The NDP says there are 131,152 eligible voters, which have four options on how to submit their ballot:

  1. Vote in advance online
  2. Vote in advance by mail-in ballot
  3. Vote online during the convention
  4. Attend the convention and vote in person

How a leader is chosen

The process by which a new leader is chosen is in equal parts simplistic and mathematically complicated.

In short: The candidate who receives more than 50 per cent of the support is crowned the new party leader.

Seems simple, doesn't it? If it were that cut and dry, however, the party would not need to host a two-day conference at the Metro Toronto Convention Centre.

It is possible, but not certain, one candidate will receive the majority of support in one round of voting. If no one is declared the winner on the first ballot, the party will continue to vote until someone is declared the winner.

Any candidate that receives less than one per cent of the vote and the candidate that receives the lowest percentage of votes in each round will be dropped from the next ballot.

And between each round of voting there is a delay of about an hour, during which trailing candidates may cross the floor to cut deals with potential winners, campaign teams will rally online for votes for the next round and independent delegates will weigh the pros and cons of switching allegiances.

Advanced voting

Party delegates who submitted their vote ahead of the convention (through either an online ballot or by mail) were given the chance not only to choose which candidate they support, but also to list their alternate choices.

Through this "preferential voting system," advance voters were given the ability to rank the seven candidates in order of preference.

If their first choice drops out of the race, their vote would switch to their second choice in the next round of voting. If their second choice is gone, their vote goes to their third choice. And so on, down their list of preferences.

Voting on the day of the election

This preferential voting system is only used for delegates who voted in advance. Those party members voting during the convention will have a chance to cast a new ballot for each round of voting.

The chance to vote in the first round closes at 9 a.m. on Saturday. One hour later, the results will be announced. Candidates have about an hour before the next round of voting closes to cut deals or rally support.

During that time, party members attending the convention in Toronto, and the large number expected to be following the election at home through the news and online can enter a new ballot, either for their previous choice or for a new candidate.

This system allows the possibility that someone who is not an early-round favourite will marshal enough support through the day to catch up and pass the frontrunner.

If Candidate A were to drop out after the first ballot, for example, all the people who supported his candidacy would be free to decide where to throw their support.

The dropped candidate, or someone in his or her camp, will often urge supporters to jump to a specific candidate – which could lead to some very interesting negotiations and horse trading at the convention on Saturday.