The poll also suggests 68 per cent of Canadians believe Harper is not honest and accountable.
When Canadians were asked: "Thinking about the following political leaders, how well would each do as prime minister?" 28 per cent said Prime Minister Stephen Harper would do a good or excellent job, while 29 per cent thought he would do an acceptable job and 42 per cent thought he would do a poor or very poor job.
For NDP Leader Tom Mulcair 27 per cent of the respondents thought he would do a good or excellent job as prime minister, 48 per cent thought he would do an acceptable job and 25 per cent thought he would do a poor or very poor job.
Trudeau came out on top. Thirty-five per cent responded he would do a good/excellent job, 38 per cent thought he would do an acceptable job and 27 per cent thought he would do a poor or very poor job.
The chair of Abacus Data, Bruce Anderson, said the poll numbers put to rest the notion that if someone doesn't have the job, they couldn't possibly do the job, and reveals a very competitive race.
Just over 40 per cent of Canadians thought Harper would do a poor or very poor job as prime minister, and that could be problematic.
"It's very high and he's been a polarizing figure, " Anderson told Evan Solomon on CBC Radio's The House.
"I think the other thing that we're seeing in these numbers is that the number of people who say Justin Trudeau would do a good or acceptable job is substantially higher than either Mr. Harper or Mr. Mulcair," Anderson said.
Abacus also tested some of the attack lines each party has been using against the other leaders to explore the weaknesses or potential weaknesses of each leader, including questions on Trudeau's judgment, Harper's honesty and Mulcair's ability to handle the economy.
On Trudeau respondents were asked: When it comes to what it takes to be prime minister of Canada does Trudeau have sound judgment? Fifty-three per cent of respondents said yes and 47 per cent said no. Respondents were also asked whether Trudeau has good ideas for the country's future. Fifty-nine per cent said yes, and 41 per cent said no.
"I think the 59% good ideas for the country really stands out for me because his critics have been quick to pounce on his statements on certain policy issues and say he's got wonky ideas, bad ideas for the country, and I think Canadians are telling us here they don't necessarily see things that way," Anderson said.
On Harper, respondents were asked when it comes to what it takes to be prime minister does Harper govern according to values you share. Only 38 per cent said yes, while 62 per cent said no. When asked whether Harper is honest and accountable, 32 per cent said yes and 68 per cent said no.
Anderson said these low numbers are a cumulative effect for the prime minister, with last year being the worst for the Conservatives since Harper came into office.
"He came into office and won his first election on the back of a movement in the country that said we need more honesty, we need more accountability," Anderson said. "I think last year has been a terrible year for the Conservative brand – and the prime minister in particular – on the question of honestly and accountability."
Anderson also said the perception that Harper is a highly partisan figure has also hurt him.
"These numbers basically put the Conservatives on watch that they need to do better if they're going to win another election," he said.
On NDP Leader Tom Mulcair, respondents were asked about his grasp on the economy and his temperament. Forty-nine per cent said Mulcair has a good grasp of how the economy works, 51 per cent said no. And it was evenly split at 50 per cent when respondents were asked whether Mulcair had the right temperament to be prime minister.
That isn't necessariloy a bad thing, Anderson said, point out "you only need about 36, 37, 38 per cent to win an election."
He said the two things that are important about these numbers for Mulcair is that a lot of Canadians "are open-minded about the prospect that he'd be a good prime minister."
As well, his potential weakness is not necessarily temperament, but his economic policies. Anderson also said Canadians in Atlantic Canada and Quebec had a lot more confidence in Mulcair's views of the economy than in the Western provinces.
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