Tokyo stocks rose Thursday morning with the benchmark index headed for its longest string of gains in nearly 30 years, as the focus turns to this weekend's election in the world's third-largest economy.

The Nikkei 225 was up 0.66 percent or 140.80 points, to sit at 21,503.85 by the lunch break, putting it on track for a 13th winning session in what would be its longest consecutive run of gains since early 1988.

Tokyo's broader Topix index tacked on 0.52 percent, or 8.99 points, at 1,733.63.

Investors have been generally upbeat on the state of the global economy with fresh record closes on Wall Street also supplying an upbeat lead for the Japanese market.

Markets have been encouraged by polls showing Japanese Prime Minister Shinzo Abe is heading for a clear victory in Sunday's election, meaning a continuation of his "Abenomics" growth strategy.

"I really think people have underestimated things," said Andrew Clarke, director of trading at Mirabaud Asia in Hong Kong.

"It's been very fashionable over the years to dismiss Japan and the equity market, and for the most part you would have been right, but this time I am not so sure," he told Bloomberg News.

The Nikkei was below 10,000 when Abe came to power in late 2012.

But it still remains far below a record close of almost 39,000 in the last days of 1989 before a stock and property market bubble collapsed. The index then began a long descent as the once red-hot Japanese economy fell into years of malaise. 

On Thursday, Nintendo shares rose 1.30 percent to 43,480 yen and Nissan was up 0.82 percent at 1,096.5 yen, boosted by a cheaper yen. 

Banks were also higher, with Mitsubishi UFJ Financial Group rising 1.55 percent to 737.2 yen and rival Sumitomo Mitsui gaining 1.09 percent to end the morning at 4,438 yen. 

Kobe Steel was down 0.36 percent at 824 yen, after news late Wednesday that European Union aviation authorities had issued a recommendation not to use parts made by the Japanese steelmaker, which has been hammered by a quality control scandal. 

Panasonic was up 1.85 percent at 1,648 yen following a report that it plans to slash costs at its LCD TV division.

The dollar strengthened to 112.96 yen from 112.93 yen in New York late Wednesday.