Liberals in at least two key seats will have their work cut out, come the federal election as new polling shows independents, who are campaigning for more action on climate change, are poised to cause considerable disruption.

Polling conducted this week in the NSW electorates of North Sydney and Wentworth shows that the incumbent members Trent Zimmerman and Dave Sharma, will, at a minimum, be pushed to preferences. Their independent challengers command 20 per cent or more of the primary vote.