
"It's a pretty resounding victory for Bernie," said Philip Robertson, chairman of Democrats Abroad in Thailand, which organized official party polling among American voters living in the South-east Asian nation.
He said Sanders won 462 votes to Clinton's 191 votes at polling stations set up in the cities of Bangkok, Chiang Mai and Pattaya from March 2-5.
The results will be compiled and combined with absentee ballots to be officially tabulated by the international chairman of Democrats Abroad, who currently resides in Bavaria, Germany.
Robertson said more overseas Democrats participated this year in Thailand than in the 2012 primary, but it was unclear whether the lopsided vote count was typical of US expatriates worldwide.
"A lot of people were really excited to vote, many for the first time," Robertson said. "People seemed very excited about Bernie and scared about (leading Republican contender Donald) Trump."
Democrats Abroad says 8.7 million Americans currently reside overseas, and the party sets aside 13 convention delegates for overseas primary voters, plus another four appointed "super delegates" from overseas.
"It's considered like the 51st state for the Democratic Party,"Robertson said.