Ms Geoghegan (21), who does not believe she broke any rules, had votes docked for overseeing an art installation this week while the election was under way.
Even so, she won with a comfortable majority.
She gained 948 votes, 244 ahead of her nearest rival, Dan Stride.
However, the results are provisional until what returning officer Victoria Nicholson described yesterday as "a bucketload of complaints" about several candidates and their campaigns are sorted.
Complainants who do not accept her rulings can complain to an independent arbitrator but Ms Nicholson did not expect any appeals to affect the outcome.
After considering three complaints about Ms Geoghegan's involvement with an art installation, Ms Nicholson ruled yesterday her presence and interaction with students at the installation site, and her name and title appearing on a poster beside it, amounted to "passive campaigning".
The OUSA contributed $166 for installation materials and Ms Nicholson also decided Ms Geoghegan had breached election rules which prohibit the use of OUSA money or resources by a candidate.
The last president to serve two full terms was Paul Gourlie in 1979-80.
Ross Blanch served 18 months as president in 1986 and 1987 after being elected in a by-election during the first year.
Other positions announced yesterday were: administrative vice-president, Brad Russell (1761 votes); finance and services officer, Dan Stride (1332); education officer, Katie Reid (2198); welfare officer, Shonelle Eastwood (977); international officer, Ivy Lim (113); campaigns officer, Dan Beck (1180); recreation officer, Sarah van Bellekom (2180); colleges and communication officer, Francisco Hernandez (1126).
A by-election will be held for the postgraduate officer's position, after the sole candidate, Kate Amore, withdrew.
