Politicians of all persuasions are heading to Christchurch East this week ahead of Saturday's byelection to replace former Labour MP Lianne Dalziel.

Labour's Poto Williams is still considered the front-runner ahead of National's Matthew Doocey.

Prime Minister John Key will be there tomorrow, although is playing down National's chances of gaining a seat Labour has held for nearly 100 years.

Labour leader David Cunliffe arrives later in the week after returning from a transtasman conference in Sydney.


Greens co-leader Metiria Turei will be there today supporting David Moorhouse.

Conservative Party leader Colin Craig will arrive today for the first day of campaigning to support Leighton Baker, a local builder whom Mr Craig called "a typical Kiwi bloke".

One of his billboards features Mr Baker's legs alongside a set of legs in men's suits.

Mr Baker is the only candidate among the 10 contenders who stood in the electorate at the last election. He was No12 on the Conservative Party list.

Mr Craig believes Labour will probably win the byelection but he was less certain of that than he was at the beginning.

He said Mr Baker was doing outstandingly well, and all things being equal he would expect him to be the candidate at next year's general election.

"He has mobilised a team, the team has been out there doing the hard yards and that is the sort of thing you want to see a candidate is able to do ... but it is also a process of building for the next general election."