Candidates were elected to fill three multi-member electorates using a single transferable vote method, known as the Hare-Clark system.

[2] The incumbent centre-left Labor Party, led by Chief Minister Jon Stanhope, attempted to win re-election for a second term after coming to power in 2001.

A third party, the ACT Greens, held one seat in the Assembly through retiring member, Kerrie Tucker.

In September 2002, Helen Cross resigned from the Liberal Party, and remained in the Assembly, sitting as an independent.

Mick Gentleman* John Hargreaves* Paschal Leahy Rebecca Logue Karin MacDonald* Steve Doszpot Steve Pratt* Megan Purcell Karen Schilling Brendan Smyth* Graham Jensen Kathryn Kelly Rowena Bew Marc Emerson David Garrett Matthew Harding Erol Byrne Thelma Janes Burl Doble (Ind) Stephanie Elliott (FRC) Lance Muir (EQP) Five seats were up for election.

Wayne Berry* Ross Maxwell Susan McCarthy Mary Porter* Jon Stanhope* Briant Clark Vicki Dunne* Ilona Fraser Bob Sobey Bill Stefaniak* Meredith Hunter Ben O'Callaghan Roslyn Dundas Roberta Wood Rose Pappalardo Adam Porter Harold Hird Julie-Anne Papathanasiou Anne Moore Mike O'Shaughnessy John Gorman Darcy Henry John Simsons (EQP) Seven seats were up for election.

Andrew Barr Adina Cirson Simon Corbell* Katy Gallagher* Mike Hettinger Ted Quinlan* Kim Sattler Lucille Bailie Jacqui Burke* Ron Forrester David Kibbey Richard Mulcahy* Gordon Scott Zed Seselja* Amanda Bresnan Deb Foskey* Charlie Pahlman Fred Leftwich Robert Rose John Humphreys Melanie Sutcliffe Helen Cross Renee Stramandinoli Simone Gray Jo McKinley Nancy-Louise McCullough Jonathon Reynolds John Farrell Robert Fearn Tony Farrell Luke Garner Ken Helm Kurt Kennedy On election night 16 October 2004, four hours after the close of polling, with 78 per cent of the vote counted, Liberal leader, Brendan Smyth, conceded defeat to Labor.

[6] Smyth conceded that the incumbent Labor Government had been returned for a second term and appeared set to win the Territory's first ever majority mandate.

[12][13] The result marked the first time in the history of ACT self-government that one party was able to win a majority in its own right.

For the Liberal Party, leader Brendan Smyth and shadow minister Steve Pratt were both re-elected.

[12] Labor gained a seat in Ginninderra, where Democrats sitting member Roslyn Dundas unsuccessfully sought re-election.

The Greens sitting member, Kerrie Tucker, resigned from the Assembly less than one month before the election.

Voting terminals were linked to a server in each polling location using a secure local area network.

In 2001 and 2004, preferences shown on paper ballots were data-entered by two independent operators, electronically checked for errors, and manually corrected if required.

This data was then combined with the results of the electronic voting, and the computer program distributed preferences under the ACT's Hare-Clark electoral system.