"Thousands of people have gone and local people are tired," she said. "More than anywhere else, this byelection campaign needs all of us."
She urged delegates to stay on to help the campaign effort.
Lianne Dalziel resigned to become Mayor of Christchurch.
Mr Anderton himself had been considered a shoo-in for the job in 2010, shortly before the first Canterbury earthquake.
But the disaster changed everything and Bob Parker stayed for another term.
Mr Anderton's campaign was boosted on Saturday by several busloads of Labour Party conference delegates and MPs who descended upon some of the worst quake-affected parts of Christchurch to canvas door to door.
They were armed with a new policy of a state-owned insurance company, which Labour leader David Cunliffe had just announced to the conference.
On Sunday Mr Cunliffe announced the 10,000 of the houses in the party's Kiwibuild policy - 100,000 homes to be built in 10 years - would be built in Canterbury within four years of a Labour-led Government taking office.
Housing spokesman Phil Twyford also unveiled a rebuild vision for New Brighton.
Labour's candidate is Poto Williams, the regional manager of the St John of God Hauora Trust, which works with family violence.
National's candidate is Matthew Doocey, a healthcare manager at the Canterbury District Health Board.
The Greens' candidate is David Moorhouse, a software developer in community health.
Leighton Baker is the Conservative Party candidate, and the only one of the field who stood in the electorate at the last general election.