With exit polls suggesting Japanese Prime Minister Shinzo Abe’s Liberal Democratic Party has won a large majority in yesterday’s election for the upper house, analysts are turning their attention to the serious problems he will have to tackle.

The conservative LDP and its New Komeito junior coalition partner are expected to win a comfortable majority in the House of Councillors, giving them control of both chambers of the Diet, Japan’s parliament.

However, with the opposition camp fragmented, the victory does not necessarily translate into widespread support for the LDP’s policies.

While Abe has promoted aggressive monetary easing to prop up the economy, many people have not benefited from his economic policies, known as Abenomics.

Critics also say the premier has yet to come up with solutions to the country’s longstanding problems such as its huge public debt, low birth rate and unstable employment, especially for women and young people.

Earlier this month, the government said the ratio of non-regular workers, including part-time and contract workers, rose to a new record high of 38.2% in 2012.

Such prolonged underemployment problems have made the birth rate fall further, critics say. It currently stands at around 1.4 children per couple, far below the replacement rate of around 2.1 needed to maintain a population size.

Despite what Abe calls “political stability”, the premier is expected to face much opposition on major issues, even within his government.

A planned sales tax increase is strongly supported by some of the premier’s cabinet ministers. But key economic adviser Koichi Hamada, professor emeritus of economics at Yale University, has reiterated his opposition to the hike.

The tax is set to rise from the current 5% to 8% in April 2014, and 10% in October 2015.

If the government decides to go ahead with the hike, “it’s going to be a real shock to the economy”, Hamada said in a speech in Tokyo earlier this month.

One of the most difficult issues the government will face is likely to be the ongoing problems at the Fukushima Daiichi nuclear power plant since the 2011 nuclear disaster.

Earlier this month, the Nuclear Regulation Authority said that radioactive water was “highly suspected” to have seeped into the ground and contaminated the sea.

The plant suffered meltdowns at three of its six reactors after it was struck by an earthquake and tsunami. About 160,000 residents have been forced to leave their homes near the plant because of radioactive contamination.