Financial markets have already factored in a Labor victory in the looming federal election, as the Coalition struggles to make up ground in the polls and business becomes accustomed to the prospect of Bill Shorten as Prime Minister.

A Sun-Herald and Sunday Age survey of 18 leading economists has urged voters to deliver whoever wins government a clear majority to ensure reforms can get through Parliament and deliver investment certainty.

The Scope panel found that confidence was likely to decline in the months leading up to the expected May poll, with firms delaying business decisions until after the election.

Labor leader Bill Shorten is committed to scaling back negative gearing. Credit:AAP

JP Morgan's Sally Auld said changes to housing, share dividend imputation and industrial relations policies under a Labor government could cause firms to pause before deciding on hiring new workers or investing in capital.