Voter support for the Abbott government has plunged across all states over the past year and is significantly behind Labor in two-party-preferred terms everywhere except Western Australia.

A Newspoll analysis published by News Corp Australia shows the Coalition's primary vote has tumbled 10 points in Victoria and South Australia, nine points in NSW, eight points in Queensland and seven points in WA.

In two-party-preferred terms based on preference flows in last year's election, Labor leads the Coalition by 60 per cent to 40 per cent in Victoria.

In both NSW and South Australia it's by 54 to 46 per cent and by 52 to 48 per cent in Queensland.

Only in WA does the Coalition have a two-party preferred lead - of 53 to 47 per cent.