How the Conservative Leadership Index works

The index gauges each candidate's support in the race to lead the Conservative Party of Canada.

Full methodology for tracking the leadership race

There are 14 candidates vying for the Conservative Party leadership. The winner will be announced on May 27.

The Conservative leadership race is a difficult one to gauge. There are 13 candidates in the running and the rules of the contest — a preferential ballot with the equal weighting of ridings — make it unpredictable.

But the data that is available makes it possible to estimate where the candidates stand. The Conservative Leadership Index combines all of this data to do just that.

The Conservative Leadership Index is an estimate of where the candidates would likely finish on the first ballot of the leadership vote if that vote occurred today. The index is calculated using the average result of four different metrics: endorsement points, fundraising, contributors and polls.


Endorsements can reflect a candidate's regional strength — the endorsement of the local MP can move votes in a riding. It is also a signal of how likely a candidate is to win. People with standing within the party are unlikely to back someone they think will not come out on top.

In the index, a candidate's endorsements from current and former provincial and federal legislators are expressed as a share of all endorsement points awarded to candidates.

Endorsement points are awarded as follows: provincial party leader (10), former provincial party leader (5), sitting MP (5), former MP (2.5), sitting provincial legislator (1), former provincial legislator (0.5), sitting senator (0.5) and former senator (0.25). Candidates also receive points for their own status.

The value of endorsements has been determined through tests of 22 recent provincial and federal leadership races.

Endorsement points are weighted by province in order to account for the Conservative leadership voting rules, which give each riding in the country equal weighting regardless of how many members it has.


A candidate's ability to raise money is a signal of organizational strength, appeal among party supporters and the health of a campaign. A candidate with more money to spend will have an easier time reaching current and potential members and ensuring they cast a ballot.

In the index, fundraising is represented as a candidate's share of all funds raised by active leadership candidates in 2017. This metric will be updated when the next set of fundraising data becomes available.


Whether a contributor donates $100 or $1,000, that contributor's vote will still only be counted once. So it is important to take into account not only how much money a candidate raises but how many people are contributing that money.

The index takes into account each candidate's share of all individual contributors who have donated to active leadership candidates in 2017. This metric will be updated when the next set of fundraising data becomes available.

In order to reflect the equal weighting of each riding, this metric is also weighted by province.


Polling in leadership races can be of mixed quality, as only a small portion of the population will cast a ballot.

Conservative supporters may mirror how members feel about a race, but they will not necessarily be the ones deciding the outcome. Members are hard for pollsters to find without access to party membership lists. The demographics of that membership, for weighting purposes, are unknown. Other methods of finding members, for example by reaching those who have donated to the party in the past, may exclude new members who have signed up with the party in the course of a campaign or those who have never donated to the party.

But despite its potential limitations, polling can provide a good indication of where things stand at any moment and can pick up on trends that may be harder to detect in other metrics.

The index uses a weighted average of recent polls, tracking each candidate's average support among decided Conservative Party members or supporters in polls conducted over the past 30 days. These polls are weighted by sample size and polls of members carry double the weight of polls of supporters.

Past performance

Results of the Leadership Index when applied to the 2012 NDP and 2013 Liberal leadership races compared to the results of the first ballot of voting.

The index has been tested against 14 recent federal and provincial leadership races in which all party members could vote.

When data for at least three of the four metrics has been available (polling was not published in every race), the index has replicated the first ballot results of past leadership votes with a median error of +/- 2.2 points per candidate.

The median error of the index in past races is less than half of that of the endorsement, contributor and poll metrics in isolation. The error is also lower than the fundraising metric. This means the index performs better than any one of the metrics that make it up.

The preferential ballot

Each riding in the country will be worth 100 points, with each candidate receiving a share of those points equal to their support in the riding.

Conservative Party members will be able to rank up to 10 of the candidates on their ballot. If no one candidate has a majority of first choice support on the first ballot, the candidate with the lowest first choice support will be dropped and their points distributed to their supporters' second choices. 

This process continues until one candidate obtains a majority of the 33,800 points available.

The index only estimates the results on that first ballot.

About the Author

Éric Grenier

Politics and polls

Éric Grenier is a senior writer and the CBC's polls analyst. He was the founder of ThreeHundredEight.com and has written for The Globe and Mail, Huffington Post Canada, The Hill Times, Le Devoir, and L’actualité.