Scott Morrison has put the economy at the centre of his election pitch to voters, saying they need to keep him as prime minister because "now is not the time to turn back" to Labor.
Opposition Leader Bill Shorten counters that his team will manage the economy in the interests of ordinary Australians, not just the top end of town.
Mr Morrison triggered the May 18 federal election on Thursday during a brief early morning visit to Governor-General Sir Peter Cosgrove.
Opinion polls are pointing to the Liberal-National coalition losing power to Labor after five-and-a-half years in office.
But Mr Morrison said there was much at stake at the election and only the coalition could deliver a strong economy and its dividends.
"It's taken us more than five years to turn around Labor's budget mess," Mr Morrison told reporters in Canberra.
"Now is not the time to turn back. Keeping our economy strong is how we secure your future and your family's future."
Mr Morrison channelled former Liberal prime minister John Howard's 2004 campaign theme by asking voters: "Who do you trust to deliver that strong economy which your essential services rely on?"
Mr Shorten said the choice was about "a bright future and a positive view of what Australians can do together" or being stuck in the past.
"What we believe in is making sure that the economy works in the interests of working and middle-class people. When everyday Australians are getting a fair go, then this economy hums," he told reporters at a family home in outer suburban Melbourne.
"My feet are firmly planted in the backyard of a Mitcham house because I understand that politics should be about the people, it's about cost of living, education, health, good jobs, renewable energy."
Having been Labor leader since 2013, he emphasised his team's unity.
Mr Shorten's first campaign stop was the Victorian seat of Deakin, held by Liberal MP Michael Sukkar with a fairly safe 6.44 per cent margin.
Mr Sukkar was one of the key movers in the August 2018 challenge against former prime minister Malcolm Turnbull.
Deputy Prime Minister Michael McCormack will focus on lower taxes, regional infrastructure and border protection to win over country voters.
Water infrastructure, including dams, will also form a key plank of the Nationals' agenda.
Having faced internal pressure over his leadership, he's not entertaining the possibility of losing his job.
"I don't intend to lose and I don't intend for the Nationals not to be in government. It's a hypothetical question," Mr McCormack said.
The Greens are casting the poll as the "climate change election".
"The Liberal and Labor parties won't take the action we need on the climate because they are too compromised by the millions of dollars they take from their big donors in the coal, oil and gas lobby," Greens leader Richard Di Natale said.
Neither the coalition nor Labor are expected to win majority control of the Senate, with half of the 76-seat upper house up for grabs.
After a national redrawing of seat boundaries, the coalition starts with a notional 73 seats (down from 74) with Labor on 72 (up from 69).
Both leaders will begin their campaigns in earnest in Sydney on Friday.
Australian Associated Press