Malcolm Turnbull is under pressure to put in a strong performance in Sunday's debate with a new poll showing Labor in front for the first time during the campaign for the July 2 election.
The latest 7News-ReachTel poll gives Labor a 52-48 two-party preferred lead over the coalition - well down on the 10-point lead to the government in January during the Turnbull honeymoon.
Until now most polls have had the parties level pegging.
Mr Turnbull - who took over the Liberal leadership in September - continues to lead Bill Shorten as preferred prime minister 55-45, but a growing number of voters (36.8%) believe the prime minister is doing a poor job.
Mr Shorten said the opposition was still the underdog in the election race.
"When you look at the number of seats that Labor's required to win in this election, 21, the sort of swing required to do that has been achieved very rarely in Australian history," he told reporters today.
"That's why I understand that we're the underdog."
Independent senator Jacqui Lambie said Turnbull had "fizzled" so far because he's being stifled by his party.
"I would really love to see the man be able to get in his boots and do it himself and show us how it is done properly. I just don't think he has been let off the strings," Ms Lambie told the Nine Network.
Mr Turnbull's wife, Lucy, who has so far kept a low profile during the three weeks of the two-month campaign, is profiled in News Corp mastheads on Saturday.
When asked if they had discussed what life might be like if the coalition were to lose the election, she replied with a firm "no".
"In a situation like an election, you just take one day at a time and put one foot in front of the other and get on with life," she said.
Mr Turnbull was to be in his own electorate of Wentworth in Sydney this morning before heading to Melbourne.
Mr Shorten was to campaign with Labor MP Rob Mitchell in his ultra-marginal seat of McEwen in outer Melbourne where he planned to announce funding for a children's health hub in Sunbury.
Both leaders were then scheduled to join AFL legend and indigenous leader Michael Long for the AFL's Long Walk ahead of the Dreamtime fixture at the MCG.
Tomorrow both men will be focused on the first full-on leaders' debate at the National Press Club in Canberra.
Mr Shorten took out the first people's forum in Sydney at the end of week one, but this will the first time they'll go head-to-head in a formal debate where they will be grilled by three senior political journalists.
Meanwhile, Mr Abbott is facing a surprise new challenger for his safe seat of Warringah on Sydney's northern beaches.
Television personality James Mathison has announced he'll stand as an independent.
"I don't think his stance and the stance of the far right of the Liberal Party reflect the community and that's what we're going to try to tap into," the former Australian Idol host told the Daily Telegraph.
