Tokyo stocks opened flat Wednesday as investors took to the sidelines ahead of the outcome of U.S. midterm elections and inflation data. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average rose 10.04 points, or 0.04 percent, from Tuesday to 27,882.15. The broader Topix index was down 1.54 points, or 0.08 percent, at 1,956.02. On the top-tier Prime Market, gainers were led by metal product, marine transportation and wholesale trade issues, while mining, oil and coal product, and nonferrous metal issues were among major decliners. At 9 a.m., the dollar fetched 145.28-31 yen co…