The leader of Thailand's People Power Party (PPP) has said his efforts to form a government are being undermined.
Mr Samak said he was confident the candidates would be cleared
Samak Sundaravej, whose party supports ousted leader Thaksin Shinawatra, said a "dirty hand" was working to prevent the PPP taking power.
The PPP won the most seats in recent national polls, but a political rival has now brought a legal case claiming that the party should be banned.
Officials are also investigating claims of voting fraud in 65 PPP-won seats.
Initial results from December's general election showed the PPP had won the most seats but not an outright majority, meaning it would need to form a coalition to take office.
The party announced on Monday that it had reached a coalition agreement with three smaller parties.
But that plan was thrown into doubt after the Election Commission (EC) announced it was investigating a total of 83 seats won by different parties, amid claims of vote-buying.
Three PPP politicians have already been disqualified.
In a further complication for the PPP, the Supreme Court has agreed to hear a claim filed by Democrat candidate Chaiwat Sinsuwong, who alleges that the PPP is a proxy for the dissolved Thai Rak Thai (TRT) party and should therefore be banned.
TRT was the party of former Prime Minister Thaksin Shinawatra and was disbanded following the coup in September 2006. Many of its members went on to form the PPP.
The court will also investigate whether the PPP broke election rules by distributing CDs of Mr Thaksin at campaign rallies.
The CDs of Mr Thaksin may have contravened regulations
"The EC's endorsement of the PPP as a political party is illegitimate, and the PPP is not qualified to contest the polls," Mr Chaiwat told the Bangkok Post.
Mr Samak, who openly supports the exiled Mr Thaksin, told domestic radio: "They are trying hard to topple us by asking the court to void the election."
He said that an "invisible and dirty hand" was interfering in the election process, but he said he was confident that the commission was investigating the issue fairly and that the candidates would prove their innocence.