New Zealand Prime Minister Helen Clark's Labour Party faces a strong challenge for the first time after nine years in power as only two hours remain for New Zealanders to cast their votes in the general elections.

The center-right National Party is hoping to oust Helen Clark and her Green allies, probably with the backing of smaller parties and some analysts predict a kingmaker role for the Maori Party, which has signaled it could work with either major party.

Just under three million people enrolled to vote and counting of the 210,000 advance votes cast by yesterday afternoon, a third more than in 2005, is now underway.

Chief electoral officer Robert Paden said the number of advance votes could be significant as it is around 30% higher than 2005.

This report from Radio New Zealand: