TOKYO, Dec 6 (Reuters) - Japan's Nikkei average is expected to open higher on Thursday, building on gains after marking a seven-month closing high in the previous session, buoyed by a weaker yen on persistent speculation the central bank will adopt bolder action. Shinzo Abe, the leader of the main opposition who is expected to win a Dec. 16 general election, has been calling for the Bank of Japan to embark on "unlimited easing" and set an inflation target of 2 percent to pull the world's third-largest economy out of deflation. His comments have weakened the yen over the past three weeks, while the Nikkei has rallied 9.3 percent, led by exporters, which benefit the most from a softer currency when overseas earnings are repatriated. The Nikkei was likely to trade between 9,400 and 9,550 on Thursday, strategists said. Bikkei futures in Chicago closed at 9,510 on Wednesday, up 0.3 percent from the Osaka close of 9,480. "Investors will be closely watching moves in foreign exchange, to see if the yen's recent weakness is sustainable," said Kenichi Hirano, operating officer at Tachibana Securities. "The Nikkei has been lifted by purchases by some overseas funds, but other funds held off. The question is whether they will become buyers, with expectations of more yen weakness after Japan's election." Prior to the market open, foreign brokers put in net buy orders of 8.4 million shares, the largest net purchase since Nov. 26. The yen was quoted at 82.44 to the dollar on Thursday after falling 0.7 percent to 82.46 yen in the previous session. It touched a 7-1/2-month low of 82.84 yen to the dollar on Nov. 22. On Wednesday, the Nikkei added 0.4 percent to 9,468.84 to a seven-month closing high. The broader Topix ended flat at 781.86. The benchmark Nikkei is up 12 percent this year, in line with a 12.1 percent rise in the U.S. S&P 500 but slightly behind a 13.2 percent gain in the pan-European STOXX Europe 600 index. > Dow, S&P higher, but Apple sinks Nasdaq in wild day > Euro falls against dollar after Spain bond auction > Treasuries firm on fiscal cliff concerns > Gold falls to one-month low no fund sales, technicals > Oil falls after U.S. gasoline inventories leap higher STOCKS TO WATCH --PANASONIC CORP, TOSHIBA CORP The European Commission imposed the biggest antitrust penalty in its history on Wednesday, fining six firms including Panasonic, Toshiba and Philips a total of 1.47 billion euros ($1.92 billion) for running two cartels for nearly a decade.