The Cook Islands prime minister, Jim Marurai, is threatening to call a snap general election if the results of next month's by-election go against the government.
The by-election will be the second in two months.
Jason Brown reports from Rarotonga.
"If the opposition wins in the Matavera by-election, the government will face a hung parliament with 12 seats on each side. The prime minister, Jim Marurai, has threatened to call a snap election to avoid giving the casting vote to the speaker of parliament. Speaker Norman George last week declared his support for the opposition. This follows the failure of links with Mr Marurai and their grouping under the Cook Islands First banner. Now, Mr Marurai is sending a clear message to voters in Matavera that a vote for the opposition could mean months of campaigning, snap elections and further political instability."