French Polynesia's opposition Union for Democracy says its rally in Tahiti ahead of next week's by-election was the biggest ever.
The party says it had 25,000 supporters marching onto Papeete while police put the figure at 15,000.
Campaigning has intensified, with the ruling Tahoeraa Huiraatira at the same time having 2,000 cars drive around the island of Tahiti in a campaign convoy.
A candidate of the Union of Democracy, Tea Hirshon, says despite provocations, the rally has remained peaceful.
"I think it is a new phenomenon in Tahiti that you have so many flags. And Flosse's party seeing all our flags decided to do the same, too. So it has become very colourful."
Tea Hirshon also says there is no guarantee that the election won't be annulled again.
She says her party has no trust in the French judiciary which annulled the result for 37 of the assembly's 57 seats following the May general election.