The Labour Party says it is confident it can re-build its majority in the Mana electorate.
Kris Faafoi held the seat near Wellington for the Labour Party with a majority of 1080 votes on Saturday night, well down on the 6000 majority secured by Luamanuvao Winnie Laban in 2008.
The National Party has claimed it is the real winner, with Prime Minister John Key saying it is unheard of for a sitting Government to record such a large swing towards it in a by-election.
Mr Faafoi says he won the by-election by just over 1000 votes because just 55% of the electorate voted. More than 82% of voters turned out in 2008 to vote for Ms Laban.
Mr Faafoi says he was never going to enjoy the same majority Ms Laban built up over nine years.
"I'm a new candidate. Winnie worked really hard to build up a 6000-vote majority ... and I've got 12 months to shore up that majority and I'm confident we'll extend that in 2011."
Mr Faafoi says he will be judged in next year's general election by his ability to respond to the concerns of Mana electorate, which include the rising cost of living, as prices increase faster than wages.
The Prime Minister says Labour's caucus will now have even less confidence in the party's leader Phil Goff.
But Mr Goff says Labour won with a first-time candidate and National's candidate Hekia Parata lost despite having stood in Mana before and having an office in the electorate for two years.
Mr Goff believes electoral fatigue following the recent local body elections could have been responsible for the tighter than expected result in Mana.
Mr Goff dismisses criticism the close race shows a swing in the traditional Labour stronghold, saying voters know a by-election does not change the Government.
