WASHINGTON — Facing a tough election, the congressman's advertisements attack his rival's support of free trade. The camera turns to a Chinese street scene and a voice intones, "As they say in China, xie xie ('Thank you')." Not to be outdone, commercials for challenger Bob Gibbs flash a Chinese flag, accusing Democratic incumbent Zach Space of allowing US stimulus money to support green technology in the emerging Asian economy. The contest in economically struggling Ohio is one of many in the November 2 congressional elections in which China has become the premier bugbear, accused of killing US jobs. A key...