The by-election occurred following the death of MP James O'Brien and was won by Jim Kent.

There were six nominations for the Labour Party candidacy:[1] The former Speaker of the House of Representatives and Auckland East MP Bill Schramm, who was defeated in 1946 and was originally from Hokitika, was also speculated as a possible candidate but later dismissed.

[1] Both declined nomination, as did Patrick Joseph O'Regan, a farmer from Inangahua Junction, owing to health reasons.

[6] Lockington was selected by a meeting of delegates and members of the Westland electoral committee at Greymouth on 28 October.

[8] The following table gives the election results: Kent obtained 57.9% of the votes and was successful.