MALCOLM Turnbull and Bill Shorten are the least wanted politicians competing for Australia’s leadership in more than 20 years, with a new poll showing nearly a quarter of voters can’t decide who would make a better prime minister.

The latest Newspoll taken for The Australian shows there has not been a less desirable pair since Paul Keating and Alexander Downer in 1994-95.

Since Mr Turnbull became prime minister in 2015 an average of 24 per cent of voters have been uncommitted on who would make a better leader.

That’s compared to the 22.6 per cent of voters who could not decide when Tony Abbott faced off against Bill Shorten and the 14.8 per cent when John Howard faced Kevin Rudd a decade ago.

Mr Turnbull’s support as the better prime minister has plunged to 41 per cent in the latest poll from the high of 64 per cent after he replaced Mr Abbott as leader in 2015.

He remains preferred prime minister, with an average of 49.9 per cent of voters who consider him the better leader since he took up the role.

But the Opposition Leader has made significant gains over the period with the latest poll showing 32 per cent of voters would consider him the better prime minister, more than double the 14 per cent in December 2015.

In the latest Newspoll, taken after the final two sitting weeks of 2016, about 27 per cent of voters did not prefer either Mr Turnbull or Mr Shorten — the equal highest level for an individual Newspoll survey since 2002.

The highest uncommitted vote was recorded in 1994-95 when Mr Keating was prime minister and Mr Downer was opposition leader.

The uncommitted vote then averaged 27.4 per cent, peaking in January 1995 at 32 per cent of voters not wanting either leader.