HARRISBURG, Pa. (AP) -- Before he ran for the Senate in Pennsylvania, David McCormick was a big name on Wall Street as CEO of the world's largest hedge fund. But McCormick's Wall Street days have provided grist for attacks by Democratic Sen. Bob Casey. Casey is pressing the case that the hedge fund invested in Chinese companies that are considered part of Beijing's military and surveillance industrial complex. But McCormick's fund was hardly alone. American investment in Chinese companies surged while McCormick was CEO. Now, each candidate is trying to show he's the tougher one on China.