Newspoll, in its first poll of the campaign, has Labor holding a commanding 10 point lead - 55-45 per cent - over the coalition.
The result is at odds with two Galaxy polls at the weekend, one showing Labor and the coalition tied on 50-50 and the other having the government ahead 52-48.
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All three polls make one consistent finding: Julia Gillard is streets ahead of Tony Abbott as preferred prime minister.
Newspoll CEO Martin O'Shannessy says the polls are showing a "very steady" result for Ms Gillard.
"She is entering the election campaign having re-established the base vote for Labor, much as Tony Abbott did for the coalition," he told Sky News on Monday.
The Newspoll, published in The Australian newspaper on Monday, and the Galaxy poll, released by the Nine Network on Sunday - showing the parties locked at 50-50 - were showing much the same result.
"I think it's just foolish to play up the differences," Mr O'Shannessy said, adding both results were subject to a three-point margin of error.
"It's a bit too early to get excited yet."
Female voters are the primary reason for a surge in support for Labor and Ms Gillard, Mr O'Shannessy said.
"That may taper off or she may go on and win men as well, but right now it's very early days."
Opposition immigration spokesman Scott Morrison said there was no doubt Labor was the frontrunner.
He also played down Ms Gillard's big lead as preferred prime minister.
"It's not MasterChef," he told ABC Radio.
"I think what people are waking up to is that they (Labor) might have changed leaders but policies haven't changed."
Finance Minister Lindsay Tanner rejects the suggestion Labor is the election frontrunner.
"You have got two fairly-new leaders," he said.
"That means there is a level of uncertainty about this campaign that hasn't been there in previous campaigns."
Mr Tanner, who is leaving politics at the August 21 poll, said
Ms Gillard remained very popular in his electorate of Melbourne.
"But as I have said to people for years, you shouldn't take my electorate as an indicator of anything about the wider community," he said.
