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Peter MacKay would perform the best out of three Conservative leadership candidates in a national election pitting him against Liberal Leader Justin Trudeau, according to a new poll conducted by Mainstreet Research.

The poll of 1,470 Canadian adults conducted on Jan. 16-17 asked them who they would vote for if a federal election were held today, with four different scenarios of who is Conservative leader: Andrew Scheer, Pierre Poilievre, Marilyn Gladu and MacKay.

While Trudeau’s Liberals are the most popular party in any of the four leadership scenarios, a Conservative Party led by MacKay, who announced his entry into the leadership race on Jan. 15, would receive 31.7 per cent of the vote. That is almost five per cent more than the next leadership hopeful.

MacKay was an MP from 1997 to 2015, serving as a senior minister in Stephen Harper’s government for almost a decade. He was the last leader of the Progressive Conservatives before it merged with the Canadian Alliance in 2003 to form the present-day Tories.

READ MORE: MacKay enters Conservative leadership race

In comparison, the Tories led by Poilievre, who has all but announced he will enter into the race, would receive 26.9 per cent of the vote in an election held today. Poilievre has been an MP since 2004 and was a minister in Harper’s cabinet from 2013 to 2015. He is now the party’s finance critic.

A party led by Gladu, who announced on Jan 9. her bid for leadership, would receive 24.1 per cent of the vote. Gladu has been an MP since 2015, serving as the Tories’ health critic since 2017, and is the only female contestant in the race thus far.

A significant number of voters remain undecided in each Tory leadership scenario.

Scheer, who is staying on as Conservative leader until a replacement is decided at the party’s convention on June 27, would receive 30 per cent with him as Tory leader in an election if it were held today. Polling on Scheer reflects the current leadership of federal parties.

The survey did not ask respondents which party they would back if Erin O’Toole as Conservative leader.

O’Toole, the Tories’ foreign affairs critic and a former minister who was first elected federally in 2012, has yet to formally announce his candidacy but has assembled a campaign team that includes Jeff Ballingall, the creator of popular conservative pages Ontario Proud and Canada Proud. Ballingall announced his role as digital director on Jan. 16.

Potential hopefuls not surveyed in last week’s polling include Rona Ambrose and Jean Charest.

Mainstreet’s poll also shows that among the three Conservative leadership candidates, MacKay would have the most backing by party supporters, of which 454 were surveyed.

A total of 86.2 per cent of Conservative supporters said they would back MacKay in an election, compared to 80 per cent for Poilievre and 70.2 per cent for Gladu. Some of that party support is either undecided or going towards the People’s Party.

Trudeau’s Liberals would receive 34.5 per cent of the vote in a federal election with MacKay as Tory leader. Liberal Party support is the highest with Scheer as leader.

The survey is intended to represent the voting population in Canada and has a margin of error of plus or minus 2.77 per cent, 19 times out of 20.

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