Known until the 2010 election as Prospect, the western Sydney electorate of McMahon covers two distinct suburban areas separated by Prospect Reservoir and semi-rural areas immediately to the west.

There is a wide variability in ethnic diversity among the electorate’s suburbs, with English speakers accounting for over three-quarters of the population in St Clair and Erskine Park compared with barely a fifth in and around Fairfield, home to large Arabic and Vietnamese populations. This is broadly reflected in income levels, with family income in the former areas roughly double those of the latter.

Prospect was created at the 1969 election, at which time it covered Liverpool some distance to the south. It was drawn closer to the city with the expansion of Parliament in 1984, during which Liverpool was taken in by the new seat of Fowler. Labor has held the seat at all times, but a weakening trend has been evident since a 5.8% swing in 2004 reduced the margin to 7.1%. This was doubled by the swing to Labor in 2007, but a 6% swing in 2010 brought it back down to 7.8%.

The area covered by the electorate turned from red to blue in the 2011 state election landslide, the only holdout being Fairfield (the majority of which is in McMahon’s eastern neighbour Blaxland), where the margin was reduced from 20.4% to 1.7%. The swings in Mulgoa, which covers St Clair and Erskine Park, and Smithfield, including Bossley Park and surrounding suburbs, were over 20%.

Prospect/McMahon has been held since 2004 by Chris Bowen, the previous members having been Richard Klugman until 1990 and Janice Crosio thereafter. His elevation to cabinet came when he filled the vacancy created by the resignation of factional colleague Joel Fitzgibbon in June 2009. He at first assumed the human services, financial services, superannuation and corporate law portfolios, before being delivered the hospital pass of immigration and citizenship after the 2010 election.

The preselected Liberal candidate is Ray King, police superintendent for the Liverpool area who served in the same capacity in Fairfield from 2005 to 2008. Fairfield councillor Frank Oliveri had initially been considered the frontrunner, but he withdrew amid an Independent Commission Against Corruption inquiry into non-disclosure of election fundraising ahead of the 2007 election. Other contenders for the preselection were Casula real estate agent Joe Romeo and the candidate from 2010, Iraqi immigrant and Fairfield grocery store owner Jamal Elishe.

A ReachTEL automated phone poll of 630 respondents in the electorate, conducted in early March to coincide with five days of campaigning in western Sydney by the Prime Minister, found Bowen to be heading for a heavy defeat with 31.8% of the primary vote against 52.5% for the Liberal Party, panning out to a 62-38 Liberal lead after preferences. A further question on how respondents would vote if Kevin Rudd was leading the Labor Party had the Liberal lead at 53-47.