The Liberal Party's primary vote has crashed in North Sydney ahead of Saturday's byelection, new polling shows, amid claims the Baird government's council amalgamation plans are driving the backlash.

The ReachTel poll taken on Tuesday night shows the Liberal Party's primary vote has fallen to 46.3 per cent - a 14.7 per cent drop from the result achieved by former treasurer Joe Hockey in 2013.

Trent Zimmerman (left) is the Liberal candidate for North Sydney after Joe Hockey quit. Credit:Jesse Marlow

The Greens are polling at 19.3 per cent, independents and others at 15.5 per cent, Fred Nile's Christian Democratic Party at 3.5 per cent and 15.3 per cent were undecided. Labor is not fielding a candidate.