Immigration Minister Peter Dutton, Small Business Minister Bruce Billson and newly elected Speaker Tony Smith are among senior government MPs who could have lost their seats had an election been held on Saturday.

As many as 36 seats held by Liberal or National Party MPs would have fallen on the back of a uniform 7.5 per cent swing, according to the latest Fairfax-Ipsos poll.

The 36 seats, more than half of which are in New South Wales and Queensland, represent 15 more than the 21 Labor would need to form government.