If Barack Obama is to push through a long-stalled US-South Korea free trade deal, he is going to need something he hasn't seen much of during his presidency: Republican support. Obama's Democratic allies in Congress are balking after his announcement last week at a high-profile global summit that he will revive the accord to cut tariffs and other barriers to trade. Democratic worries about South Korean restrictions on auto and beef trade sank the agreement after Republican George W. Bush's administration and Seoul signed it three years ago. It now has Obama's support, but his party still shows little enthusiasm ahead of November's congressional elections. Labor unions and other core Democratic supporters say foreign trade agreements steal American jobs. That puts Obama in the unusual position of relying on help from Republicans, who have opposed in near-perfect unison his biggest initiatives, including his overhauls of health care and financial regulations. Republicans traditionally favor foreign trade deals more than Democrats do, and they are lining up behind Obama's push to settle a pact that the White House says could boost exports of American products by $10 billion a year. It would be the largest US trade deal since a 1994 agreement with Canada and Mexico. Republican Rep. Dave Reichert says the Korea accord “has the potential to create thousands of American jobs and continue a partnership with a democratic ally.” At the Toronto summit of the Group of 20 economies, Obama directed his trade envoys to work out differences with their Korean counterparts by the time he visits Seoul in November for the next G-20. That would let him send a deal to Congress early next year. House Rules Committee Chairwoman Louise Slaughter, a Democrat, expressed surprise that Obama would “try to slide this poorly written trade deal past the American public when Congress has already said that the deal is not good for our economy or workers.” Opponents say the accord does not knock down enough barriers to the sale of US-made cars in Korea. There also is frustration with South Korean restrictions on American beef imports. Bowing to those worries, Obama initially refused to send the deal to Congress for a vote. Then, early this year, Obama championed a drive to double US exports during the next five years. Part of that push, he said, would be strengthened trade ties with South Korea. Now, after Obama's commitment in Toronto, he must win over Democrats. Supporters contend the deal would strengthen ties with an important US ally at a moment of high tension on the Korean peninsula. The United States wants to bolster Seoul after a South Korean-led international investigation found that a North Korean torpedo sank a South Korean warship in March, killing 46 sailors. During the G-20, Obama lavished South Korean President Lee Myung-bak with attention. Besides the trade deal, Obama announced an agreement, coveted by the Koreans, to delay until 2015 a plan for the US military to hand over to Seoul command of troops on the Korean peninsula if war should break out between North and South Korea. Obama also criticized North Korea over the sunken warship. “There is a foreign policy imperative to move forward with the ratification of this agreement,” said Jeffrey Schott, senior fellow at the Peterson Institute for International Economics. Another White House argument will point to Seoul's warning that the United States could lose hundreds of thousands of jobs if it should fail to act and a South Korean trade agreement with the European Union were ratified. It is unclear how far South Korea is willing to bend in talks with Washington. Seoul says it will not renegotiate the deal; officials will pursue “adjustments,” clarification of the text and possible side deals. On the accord's biggest hurdle, economist Schott said complaints about South Korean trade barriers on autos are exaggerated. “The overwhelming broad economic and foreign policy benefits this will bring shouldn't be held up by the protectionist concerns” of auto companies and unions, Schott said.