The public broadcaster said a candidate and former prime minister Manuel Valls contacted the French Polynesia president Edouard Fritch and asked him to hold them for the sake of democracy.
The party struggled to finalise plans for primaries but now four locations will open for the vote.
When the primaries were last organised by the pro-independence Tavini Huiraatira, there were 200 polling stations.
Manuel Valls, who served under the outgoing President Francois Hollande, is seen as the front-runner for the nomination.
The centre-right Republicans have selected Francois Fillon as their nominee.
Mr Fritch, who endorsed a losing Republicans’ candidacy, has expressed alarm at Mr Fillon’s plans to slash public sector spending.