TOKYO (Reuters) - Prime Minister Shinzo Abe's Liberal Democratic Party (LDP) and its junior coalition partner appear on track to win a majority in a July 21 election for parliament's upper house, cementing the Japanese leader's grip on power and ending a parliamentary deadlock that has foiled policy implementation since 2007.
Abe, 58, returned to office for a rare second term after the LDP won a December election for the more powerful lower house.
Attention will be focused on whether the LDP can win a majority on its own in the 242-seat upper house chamber, where half the seats are being contested. The LDP and parties in favor of revising the pacifist constitution are also looking to win the two-thirds majority necessary to submit revisions to a national referendum.
The LDP holds 50 of the seats that are not up for re-election and needs to win 72 out of the 121 seats being contested to obtain a majority. The LDP and other pro-constitutional revision parties need to win 99 seats out of 121 being contested to obtain a two-thirds majority of 162.
Here are key facts about Japan's political parties:
LIBERAL DEMOCRATIC PARTY OF JAPAN (LDP)
2012 lower house election result: 294 out of 480 seats
The LDP returned to power after a three-year hiatus. Until the 2009 election, the party, which has nurtured close ties with business and the bureaucracy, had been in power alone or in coalitions almost non-stop since it was founded in 1955.
Support for Abe and the LDP has remained high on hopes for his "Abenomics" prescription to end decades of economic stagnation with a combination of hyper-easy monetary policy, fiscal spending and "Third Arrow" structural reforms, including deregulation. However, doubts simmer about whether the LDP will really follow through with bold reform steps.
While public opinion favors phasing out nuclear energy after the 2011 Fukushima disaster, the LDP has adopted a pro-nuclear energy policy, promising in its platform to make efforts to win local support to restart reactors taken offline after the world's worst atomic disaster since Chernobyl.
The hawkish Abe wants to revise Japan's U.S.-drafted, post-war pacifist constitution, part of a conservative agenda that aims to restore traditional values and revive national pride.
Initially seen as a hardliner in a row with China over disputed isles, Abe has stressed his door is open for dialogue.
Abe ended his first 2006-07 term as premier by quitting abruptly after a year marred by cabinet scandals, public outrage over lost pension records, a huge upper house election defeat and ill health.
Established: 1964 (predecessor Komeito set up)
2012 result: 31 lower house seats
The party, founded by members of the Soka Gakkai Buddhist sect, was a junior partner in LDP-led governments for 10 years until the ruling camp's rout in a 2009 lower house election. It returned to power with the LDP in December and the two parties hold a two-thirds majority in the lower house.
Some in the LDP would like eventually to end the alliance, given policy differences, but cutting ties would not be easy as the two parties have cooperated closely in election districts, with the LDP relying on the Komeito's solid vote machine to provide support for many of its own candidates.
The New Komeito focuses on economic policies for the less well-off and is more moderate on security issues than the LDP, being cautious about revising the pacifist constitution.
DEMOCRATIC PARTY OF JAPAN (DPJ)
2012 election result: 57 lower house seats
Formed in a merger of several opposition parties, the DPJ swept to power in 2009 to end more than half a century of almost unbroken LDP rule. But disillusioned voters shunned the party in the December poll, in which it won less than a fifth of the seats in 2009, when it promised to pay more heed to consumers than companies and pry control of policies from bureaucrats.
The Democrats' support slumped over what voters saw as broken promises, a confused response to the 2011 tsunami and nuclear crisis and its embrace of unpopular causes such as a sales tax hike and the restart of nuclear reactors. The party split over the planned tax rise in 2012, with defectors led by former party leader Ichiro Ozawa setting up a new party, the People's Life Party.
The Democrats are now fighting for their political life. Some experts wonder whether the party can survive another big election loss, while others say it has a chance to regain support if "Abenomics" fails to cure Japan's economic ills.
In contrast to Abe's stress on hyper-easy monetary policy, the Democrats want to boost disposable income to increase domestic demand and beef up social security to ease anxiety about the future that depresses spending. The DPJ also targets giving up atomic energy by the 2030s.
JAPAN RESTORATION PARTY
Website: http://j-ishin.jp/(Japanese only)
2012 election result: 54 lower house seats
Populist Osaka Mayor Toru Hashimoto, 44, launched the right-leaning party last September to woo voters fed up with the two main parties. His core policies include shrinking the role of the central government, more market competition and cuts in corporate and income taxes.
The party then merged with a few conservative lawmakers led by nationalist former Tokyo Governor Shintaro Ishihara, 80, in a bid to build an influential "third force".
The party has been seen as a possible ally for Abe's push to revise the constitution but its fortunes faltered after Hashimoto's comments appearing to try to justify Japan's wartime military brothels, where many Asian women were forced to work.
Website: http://your-party.jp (Japanese only)
2012 election result: 18 lower house seats
A centre-right party founded by former LDP lawmaker Yoshimi Watanabe, the party favors small government and free market-oriented economic policies including deregulation.
It also agrees with the LDP on the need to lower hurdles to revising the constitution, but does not place top priority on the contentious changes.
The party wants to freeze a planned rise in the 5 percent sales tax from 2014 and aims to exit nuclear power in the 2020s.
Other parties running candidates include the Japan Communist Party, the People's Life Party, the Green Wind Party and the Social Democratic Party. All want to give up nuclear power and oppose the sales tax rise and Japan's entry into talks on the U.S.-led Trans-Pacific Partnership free trade pact.
(Writing by Linda Sieg; Editing by Clarence Fernandez and Raju Gopalakrishnan)
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