But international observers have said there was nothing to suggest
"According to the exit polls and all the data, we have won," Saakashvili told hundreds of cheering supporters at his campaign headquarters in Tbilisi, the capital on Saturday.
Election chiefs were not expected to announce the first, preliminary results until early on Sunday, but Saakashvili's supporters already piled out onto the streets of Tbilisi, sounding car horns and waving the national flag.
According to Tina Khidasheli, one of the opposition's leaders, people were filmed voting two or three times and that some ballot boxes had been tampered with by election officials.
|Gachechiladze says he has won|
the presidential vote[AFP]
"The authorities are trying to remove any legal basis for contesting the election," Khidasheli said.
She also claimed that election officials were refusing to register complaints made by opposition representatives at polling stations.
But the central election commission (CEC) denied on Saturday that there had been any problems.
"The elections are proceeding in a calm atmosphere without any serious violations," Irakli Porchkhidze, a spokesman for the CEC, said in televised comments.
Gachechiladze, who heads a nine-party coalition which accuses Saakashvili of economic mismanagement, corruption and autocratic rule, said on Friday that he may not recognise the results.
As the president claims victory, so did he, and he has asked people to celebrate his win at a rally in Tbilisi.
"Today we actually won in almost every precinct, according to our information," he said.
Exit poll validity
Claims of media bias and the use of state resources to support Saakashvili's bid is also a factor as to why the opposition is contesting the results.
The exit poll was conducted by a Georgian university, a public affairs institute and two leading think tanks.
Financing was provided by four television companies, including the state-financed Georgian Public Broadcaster, while six local research groups did the field work.
The opposition says the poll could not be trusted because all four television channels are allegedly pro-government.
Poll organisers deny any bias.
Elehie Skoczylaz, a US consultant to the organisations carrying out the exit poll, defended the way it was conducted.
She said: "This was professional, objective and there was no interference."