Bruised by months of financial scandals, a cost-of-living crisis and unpopular leaders, some might be forgiven for expecting to see the end of Japan’s beleaguered ruling Liberal Democratic party (LDP), which has been in office for most of the past seven decades.

The election on 27 October will take place a year earlier than many had expected, following the surprise resignation of the former prime minister, Fumio Kishida, following record low approval ratings and public anger over his party’s apparent addiction to in “money politics”.

His successor, Shigeru Ishiba, was selected last month by party MPs and rank-and-file member to revive the LDP’s fortunes and douse the flames of a factional war that saw Ishiba narrowly fend off a challenge from the party’s right.

Yet even at a time of political turmoil, polling suggests many believe the party will go into the 465-seat lower house election reasonably confident it would be returned to office for the fifth time in succession.

Some polls even showed the LDP would retain its majority, aided by a projected low turnout and a divided opposition. A poll last weekend by the Kyodo news agency put the LDP on 26.4%, well ahead of the main opposition Constitutional Democratic party on 12.4%.

However, a new poll by the Nikkei suggests the party could fail to secure a majority – a result that the business newspaper says would “potentially set the stage for political turmoil not seen since 2009”, which is the last time the party lost a lower house election.

The LDP is aiming to retain at least 233 seats to secure an outright majority – a modest ambition given its current total of 256 seats.

A PM under pressure

The party’s dominance of Japan’s postwar political landscape has not been absolute. In 2009, voters ousted the LDP in a shock result that saw the left-of-centre Democratic Party of Japan (DPJ) take office under prime minister Yukio Hatoyama. For once, the traditionally fragmented opposition had achieved a level of unity that made the DPJ a serious electoral prospect.

Analysts attributed the DPJ’s victory to fallout from the 2008 global financial crisis, a growing income gap, a damaging scandal over the loss of millions of pension records and the LDP’s deeply unpopular prime minister, Taro Aso, whose cabinet approval rating going into the election sank to just over 16%.

The LDP’s time in the wilderness was short lived, however. Hatoyama lasted less than a year, forced out by his failure to realise a campaign pledge to reduce the US military burden on the southern island of Okinawa. His two successors fared little better, and at the end of 2012 normal service resumed with the election of an LDP government led by Shinzo Abe.

Tobias Harris, founder of the advisory firm Japan Foresight, said Ishiba could struggle to introduce legislation if the LDP and Komeito together lose enough seats to weaken the coalition’s control of key parliamentary committees.

That would “not only fundamentally undermine his claims to be an electoral asset for the party … but would also compromise any efforts to clean up and modernise the party and unify it under his leadership”, Harris said.

Ishiba’s victory in the LDP leadership race raised hopes that a gentler version of LDP would emerge from the upheaval of recent months. He is widely seen as a moderate alternative to the ultra-conservative Sanae Takaichi, his main rival.

The 67-year-old, a softly spoken former banker whose hobby is making model warplanes and ships, had indicated he supported same-sex marriages, reigning empresses and the right of married couples to use different surnames – social and cultural shifts his party has opposed, in defiance of public opinion.

Ishiba had also vowed to take tough action against LDP lawmakers who plunged the party into crisis after revelations they had siphoned unreported profits from the sale of tickets for party events into secret slush funds. Concerns linger, too, over his party’s ties to the scandal-hit Unification church.

But in an apparent attempt to placate his rightwing opponents inside the LDP, Ishiba has backpedalled since becoming prime minister, telling parliament last week that changing the law on married surnames – in which women almost always take their husband’s name – and the ban on gay marriages “require further examination”. He refused to comment on any reforms to Japan’s male-only succession laws.

Critics have also accused him of abandoning promises to address the funding scandal. The LDP has refused to endorse 12 candidates found to have committed the most serious misdemeanours but will not oppose them at the election. Ishiba has said they may even be welcomed back into the LDP fold if they win.

And while a record 314 women will be competing for seats – female MPs currently make up just over a tenth of all lower house members – the lower house is not expected to look dramatically different. About 10% of all candidates hail from political families, including Ishiba, who “inherited” his father’s former seat in rural Tottori prefecture in 1986.