A leading New Caledonian member of the French UMP Party, Gael Yanno, has welcomed the election of Jean-Francois Cope as party president as his rival, Francois Fillon, now claims to have secured a majority.
The leadership contest to lead the French opposition party follows this year's presidential election defeat of Nicolas Sarkozy.
After Mr Cope had been declared the winner of the internal party vote, it emerged that the votes by 1,300 members in three overseas territories, including New Caledonia, had not been counted.
According to Mr Fillon's backers, he had secured more than 88,000 votes, 26 more than Mr Cope.
The row risks to split the party, prompting calls for a former foreign minister, Alain Juppe, to become the interim leader.
In the 2007 presidential election, the UMP's Nicolas Sarkozy scored his best result of any electorate in New Caledonia.