PREMIER Barry O'Farrell's move to dump lord mayor Clover Moore from State Parliament has backfired, with her chosen successor, the independent Alex Greenwich, romping to victory in the Sydney byelection.

More than 48 per cent of people voted for the independent and, after preferences from the Greens candidate Chris Harris, Mr Greenwich finished with a two-party preferred vote of just under 65 per cent.

Celebration ... Alex Greenwich is congratulated by Clover Moore and other supporters after winning the Sydney byelection.

Mr Harris said: ''The Greens are delighted that a progressive candidate continues to hold the seat.''

Labor's decision not to run a candidate appeared to have delivered an easy win to Mr Greenwich.