Liberal Leader Justin Trudeau is brushing aside an NDP-commissioned poll that shows him trailing the NDP candidate in the Montreal riding of Papineau, while another survey has him slightly ahead.

The poll -- which circulated just as the leaders were making their finally preparations for a debate Thursday -- has journalist Anne Lagace Dowson in front with 46 per cent support, compared to 35 per cent for Trudeau.

"I look forward to hearing what happens as the NDP candidate in Papineau actually goes door to door and tries to explain that the NDP isn't going to help anyone now," Trudeau reporters in Montreal Friday.

Trudeau emphasized at a debate in Calgary Thursday that his plan includes "modest deficits" to allow large, immediate investments in infrastructure like roads and transit, in contrast to the NDP, which would spend less to balance the budget.

Trudeau said he had been a "strong voice" for Papineau residents, adding he will "continue to work hard" to "make sure that their concerns about affordable housing, help for our more vulnerable seniors (and) public transit … are highlighted."

NDP Leader Tom Mulcair, meanwhile, told reporters in Regina that Lagace Dowson is a "phenomenal candidate" and that the poll "reflects what we’re seeing on the ground."

"We really do have the intention of winning Papineau," Mulcair said.

However, a new poll released by Mainstreet/Postmedia on Friday runs against the results of the CROP poll and suggests that Trudeau remains the frontrunner in his home riding.

Among all voters, the poll found that Trudeau has a five per cent lead over Dowson. The Liberal leader received support from 33 per cent of respondents, while Dowson trailed with 28 per cent.

Undecided and leaning voters also favoured Trudeau: He received 41 per cent support to Dowson's 36 per cent.

The Mainstreet/Postmedia poll surveyed a random sample of 783 Papineau residents through a mixture of landlines and cellphones on Sept. 17.

Its margin of error is 3.49 per cent, 19 times out of 20.

Meanwhile, the CROP poll surveyed 375 residents over the phone between Sept. 11 and 14 and has a 5.06 per cent margin of error.

It had the Bloc Quebecois candidate trailing Trudeau and Dowson in third place with 10 per cent support and the Conservative candidate with just five per cent.

Federal party leaders have lost their seats in the past. Liberal Leader Michael Ignatieff came in second in the Toronto riding Etobicoke-Lakeshore in 2011, with 35 per cent of the vote, compared to Conservative Bernard Trottier’s 40 per cent.

And Prime Minister Kim Campbell lost her Vancouver Centre seat in 1993, when she managed to get only 25 per cent of the vote, compared to the Liberal’s Hedy Fry, who took 31 per cent and has held the seat ever since.