Move Forward Party candidate Pongsathorn Sornpetnarin had a clear victory in the Rayong by-election on Sunday, with increased support for the party, according to unofficial results.
The by-election was held in constituency 3 to fill the void left by Nakhonchai Khunnarong, also from the MFP, who resigned his seat due to a past conviction and prison term for theft.
Mr Pongsathorn received 39,296 votes, well ahead of Banyat Jetnajan of the Democrat Party, who received 26,466 votes. A far distant third was Ruengchai Sombatphuthorn of the Nation Building Labour Party with 881 votes, accortding to Klang district chief Kanjaras Iadthongsai.
Mr Pongsathorn received 12,830 more votes than Mr Nakhonchai did when he won the seat in the May 14 general election.