Support for an Indigenous voice to parliament is slipping, but a narrow majority still favours the move, a special Newspoll has found.

Backing for the voice fell from 56 per cent at the start of the year to 53 per cent in the latest survey, the poll for The Australian shows.

The total vote for those against the proposal rose only a point to 38 per cent but those saying they were strongly in favour of the proposal fell from 28 per cent in February to 25 per cent in the latest poll.

This was driven by a decline in Coalition voters who said they were strongly in favour last time – from 13 per cent down to 10 per cent.

Among the total number of voters either strongly or partly in favour, the largest decreases since February were among women, Labor voters and the younger demographics.

Among those aged 18-34, support fell from 70 per cent at the start of February – when Newspoll first asked this question of voters – to 64 per cent in the most recent survey.

A total of 57 per cent of over-65s said they were opposed in early February but that has fallen to 48 per cent now, with a two-point rise among those supportive to 42 per cent.

Women voters in favour also fell from 60 per cent to 54 per cent while support among men dropped from 53 per cent to 50 per cent.

When divided along party lines, the level of support among Labor voters dropped from 74 per cent to 68 per cent.

The number of Labor voters against the voice rose three points to 21 per cent while there was a three-point rise to 11 per cent of those Labor voters sitting on the fence.

Movement among Coalition voters saw the number in favour falling by just two points to 35 per cent.

The Newspoll of 1530 voters across the country was conducted between March 1 and March 4.