Voting officially opened yesterday with almost half a million people casting their ballots ahead of the May 3 election.

Yesterday was also the third debate between our two federal leaders.

Australian National University Political Scientist Dr Jill Sheppard told Luke Bradnam on 4BC Breakfast, "It felt like they were trying to have a bit of a crack in these last few weeks of the campaign, one week and a half to go now and they probably should have done that much earlier."

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