Scott Morrison calls 2022 federal election for Saturday May 21

Prime Minister Scott Morrison has visited Government House to formally ask Governor-General David Hurley to dissolve parliament.

Mr Morrison is seeking the Coalition's fourth term in office, while Anthony Albanese leads a Labor party which is ahead in all polls but has been in opposition for nearly nine years.

Trust is again the Coalition's central re-election theme amid a string of natural disasters and war, with the Prime Minister stating why he loves Australia and pitching himself as a safe pair of hands in uncertain times.

"You always have setbacks. You always have imperfect information. I mean, things are tough," Mr Morrison said in social media ad published late on Saturday.

"Forty-thousand people are alive today because of the way we managed the pandemic, 700,000 people still have jobs and countless numbers of business that would have been destroyed.

"This is why, as we go into this next election, what's firing me up - we're actually in a really strong position."

READ MORE: Live blog: latest news as PM calls election

All MPs in the House of Representatives and half the Senate will face re-election.

In the 151-seat House of Representatives, a minimum 76 seats are needed to win government. With recent seat changes, the Coalition currently has 76 seats and Labor has 69. There are six cross-benchers.

According to ABC election analyst Antony Green, Labor needs a uniform swing of 3.1 per cent to finish with more seats than the Coalition, and 3.3 per cent for a majority. A uniform swing is far from assured.

Mr Albanese said on Saturday that Labor had only won government three times from opposition since the Second World War.

"So, it's a mountain that Labor has to climb," he said.

"The government goes into this election as favourites. Governments win and get re-elected much more often than governments change hands in this country. And Scott Morrison has a considerable advantage in going into this election."

The opposition leader accused Mr Morrison of treating the election as a game and accused him of avoiding scrutiny.

"This Prime Minister last year gave up on governing and said he was campaigning," he said.

The three Labor leaders who have won government from opposition are Gough Whitlam, Bob Hawke and Kevin Rudd.

If Mr Albanese wins in 2022, he will be the first Left leader to lead the party to victory from opposition.

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