The leader of French Polynesia's Union for Democracy, Oscar Temaru, says he has secured the support of one more member of the assembly.
Mr Temaru says Patricia Jennings who had joined the Alliance for a new Democracy, or ADN, is back in his camp.
The move follows a by-election in Tahiti which left both main parties two seats short of a majority.
Mr Temaru says he may get one more member.
"I got Patricia Jennings over the telephone this morning. She was in Raiatea and she confirmed that she belongs to the UPLA. so that is 28 and 27 on the other side, and I am waiting for a call from the mayor of Arue, normally would call me up tonight, so we will see."