U.S. Democratic presidential nominee Barack Obama is expected to reverse his opposition to the ratification of a free trade deal with South Korea if he is elected, Yonhap News reported quoting a U.S. scholar Tuesday.

"Obama's supporters have sought to nuance the candidate's trade position _ hinting, for example, that he will reverse his protectionist position if elected," Bruce Klingner, a senior research fellow at The Heritage Foundation, said in a column for Yonhap News Agency.

Klingner noted that "Obama's comments have changed from initially simply opposing the FTA to a more nuanced discussion commenting favorably on free trade globally but rejecting the KORUS FTA as currently written."

Klingner's remarks are in line with the optimism by South Korean and U.S. officials that Obama and other congressional Democrats will approve the biggest free trade agreement for the U.S. since 1993 despite Democrats' reluctance to support the deal in a sensitive election year.

Seoul and Washington have expressed confidence that the bilateral FTA, signed in June last year, will be ratified once it is put to a vote during a lame duck session after the Nov. 4 election.

South Korean officials have said that more than 60 Democratic congressmen will vote for the Korea-U.S. FTA, giving a clear majority despite some reluctant Republicans.

Lawmakers of South Korea's ruling Grand National Party, holding a majority in the unicameral National Assembly, said they will ratify the FTA bill during the ongoing parliamentary session.

Many Democrats oppose the FTA, citing an imbalance in auto trade at a ratio of 700,000 to 5,000 sales per year against the U.S. They also want more steel shipments to South Korea.