The first of two election polls released on Saturday indicates that if the next government was to be a coalition, 42% of voters would prefer a National-led government.
A Labour-led government is preferred by 36.6%, but 21.3% are undecided.
The RadioLIVE-HorizonPoll surveyed 887 voters between Tuesday and Friday morning this week.
The margin of error is plus or minus 3.3%.
Meanwhile a Herald-Digipoll has found voters supporting National would enable it to govern alone, with 53.5% of decided voters, up slightly on a poll in August.
Labour has 30.3% support, down slightly, but support for leader Phil Goff has risen slightly from 11.5% to 13.7%.
National leader John Key's support remains at 70.6%.
The Herald-Digipoll surveyed 750 voters between 20-27 October.