Smaller towns include Ballan, Blackwood, a part of Burrumbeet, Buninyong, Clunes, Creswick, Daylesford, Myrniong and Trentham.

Ballarat’s boundaries abut the electorates of Bendigo in the north, Gorton, Lalor and McEwen in the east, Corangamite and Corio in the south and Wannon in the west.

Apart from Wannon, held by the Liberals’ Dan Tehan, the entire area is an Australian Labor Party stronghold.

Steve Gibbons holds Bendigo, Brendan O’Connor has Gorton, Rob Mitchell has McEwen and Corio is held by Richard Marles, all ALP members.

Corangamite is the most marginal seat in Australia, held for Labor by former Ballarat City councillor Darren Cheeseman by just 0.3 per cent, while the member for Lalor is former prime minister Julia Gillard.

The Mackerras pre-election pendulum, based on the 2010 election results and any significant changes since, shows Corangamite and Wannon to be marginal seats, Bendigo and McEwen are rated fairly safe, Ballarat and Corio are considered safe and Lalor and Gorton very safe.

But the bottom line of any election is not the electorate statistics but the demographics of the voters.

Who will decide if incumbent Catherine King holds Ballarat? Who will vote for Liberal challenger John Fitzgibbon? Or will there be a swing to one of the other eight candidates in a large field?

Based on the 2011 Census figures, the Ballarat electorate has 141,318 people, of which 68,607 are male and 72,711 are female, with a median age of 38.

There are also 37,051 families, with an average of just under two children per family. 

The median weekly household income is $1013, with median monthly mortgage repayments of $1387.

So how, traditionally, will these demographics affect our voting patterns?

University of Melbourne political science lecturer Scott Brenton said a young electorate, such as central Melbourne, usually correlated with a strong Greens vote.

However, he said Ballarat’s median age of 38 would place it in the middle or just towards the older end of the spectrum.

“Labor is not polling too badly in the middle age groups but it drops off in the older age groups,” Mr Brenton said.

He said Ballarat’s household income was at the lower end of the scale but its link with party preferences was not so straightforward.

“Higher income electorates often favour the Liberals but it’s not the opposite at the other end, as there are many low-income rural electorates with Liberal/National members.

“A more telling stat is often the proportion of mortgages, which tends to be higher in marginal seats, elevating the issue of interest rates.”

fiona.henderson@fairfaxmedia.com.au