Howard told 1,700 people at his ruling coalition's campaign launch that "a re-elected coalition government will, subject to economic conditions and the state of the budget, look to make contributions from future budget surpluses to these tax-free home savings accounts".
First-time buyers
Home ownership is proving increasingly difficult for many of Australia's 21 million people after 10 successive quarter-percentage point interest rate increases since early 2002.
The rate has been raised six times since Howard last went to the polls in 2004, when he promised to keep rates at record lows.
A poll in The Australian, a national newspaper, showed Howard's coalition was trailing Labor 45 per cent to 55 per cent.
The weekend nationwide random telephone survey of 1,694 voters has a 2.5 percentage point margin of error.
Howard, Australia's second-longest serving prime minister after holding the office for almost 12 years, has been trailing Kevin Rudd, the opposition Labor Party leader, in surveys all year.
Rudd will be under pressure to also offer help to first-time home buyers when he launches Labor's campaign on Wednesday.
Both Howard and Rudd are starting out in Brisbane, the capital of Rudd's home state of Queensland, a choice that underscores the Liberal-dominated state's importance to the result of the coming election.
Queensland produces much of Australia's largest export, coal, and miners' futures are uncertain as Australia plans to reduce its greenhouse gas emissions.
Polling starts
Elsewhere in the country, voters in a tiny outback settlement cast the first ballots in the elections as mobile polling teams headed out across the country to cater for voters in more remote areas.
The votes cast by scores of Aborigines in Kybrook Farm, south of Darwin, marked the start of early voting for those unable to make it to polling stations on November 24, election day, and for Australians abroad.
George Huddlestone, the first to cast a ballot at Kydbrook, said he had voted for Howard in the last election in 2003 but objected to the government's move this year to seize control of remote Aboriginal communities.
"I voted Liberal last time but Howard, he's changed the rules on us," Huddlestone told the national AAP news agency.
"Some things are changing and people are worried for their families, they don't like the changes."
He said he hoped Rudd would win the election "and things can go back to normal".
But Howard's government prides itself on its economic record and claims responsibility for a long-running boom and Australia's lowest unemployment figures in 33 years.
Many polls have positioned Howard in the lead over Rudd on the question of who is best able to manage the economy.