Both have something to prove, but in a seat that is one of Labor's heartlands Barry O'Farrell may have less to lose politically.

Meeting constituents with his candidate, Dai Le, on Monday, Mr O'Farrell said a good omen or two was making him ''feel lucky''.

''One of the residents here commented earlier that the last Opposition leader to take Cabramatta seriously was Nick Greiner, then he went on to win the election,'' Mr O'Farrell said.

Mr O'Farrell also said it was important the voters of Cabramatta were given a strong candidate as an alternative to Labor.

''Cabramatta will be a challenge of Himalayan proportions, but if we can scale it we can shake the Labor Party out of their complacency,'' he said.

Mr O'Farrell said Dai Le brought youth, enthusiasm and local knowledge to the position.

Mr Rees said that despite fielding an older candidate in Mayor Nick Lalich, Labor would be taking a ''fresh approach''.

''There is no doubt this is going to be a tough campaign and families in Cabramatta can be assured we're not taking them for granted,'' Mr Rees said.

The four byelections to be held on October 18 will be the first indication of public reaction to the string of resignations, sackings and upheaval in the NSW Government over the past month.

The Labor and Liberal candidates will also be up against independents Joseph Adams and Alasdair McDonald, the Greens' Lindsay Langlands and Christian Democrat Doug Morrison.