Abe, who has held power for five years, has seen his popularity fall significantly in the wake of the scandals. His decision to call a snap election, analysts say, is aimed taking advantage of a recent uptick in ratings.

"In theory, Abe has more than a year left (in office), but he is aware of the fact that his support levels are unlikely to improve much more," said Koichi Nakano, a professor of Japanese politics at Tokyo's Sophia University.

"He has been pushed into a corner by the scandals and he is afraid that once parliament is reconvened, he will face further questioning and another sharp drop in the polls."

Florian Kohlbacher, North Asia director of the Economist Corporate Network, said Abe is also likely hoping to avoid any potential impact the abdication of the Emperor would have on an election next year.

Constitutional changes

The crisis over North Korea has forced the country to re-examine its defense strategy.

Abe wants to remove restrictions on the country's Self Defense Forces, the de facto military, as they engage in more exercises and other activity with US and allies amid growing tensions with North Korea.

"Abe will keep keep a fairly low profile on (constitutional issues) and focus on emphasizing stability and the success of his Abenomics reforms," Kohlbacher said.

Changing the constitution requires a two-thirds majority of both houses of the Diet and a national referendum. At present, the ruling LDP-Komeito coalition holds two thirds of the lower house, 316 seats.

"Abe is aware of the fact that the people do not consider the revision of the constitution a priority issue," Nakano said.

"That's precisely why he is hoping that if he sneaks the issue through in a snap election, he can then say that he has the popular mandate to go ahead with his plans."

Uncertain standing

However, a massive 42.2% of respondents said they had not decided who to vote for, setting the ground for a potential swing against Abe.

A large majority of respondents -- 78.8% -- also said they were unhappy with the government's explanation of the land-sale scandal.

Nor were most respondents happy with being asked to choose a new government, with only 23.7% supporting Abe's decision to call an election.

Abe is hoping to take advantage of the "complete disarray" among his main opposition parties, Kohlbacher said, but he warned the risk from the new Koike-linked party "is perhaps higher than Abe thought."

"There is substantial risk for him," he said. "But that risk is only going to grow as the new party forms and develops."

Nakano said the party's potential influence may be overstated however, pointing out that it does not involve any new faces and is likely to take votes from both the LDP and Democratic Party.

Economic wins and woes

As well as the North Korea issue and his desired constitutional changes, the other main plank of Abe's election campaign will be his economic record.

Japan's gross domestic product (GDP) grew at an annualized rate of 2.5% in the three months through June. That was significantly higher than analysts had predicted and means Japan has now recorded six straight quarters of expansion.