Japan's main opposition Democratic Party looks headed for victory in an August 30 election that could end more than five decades of almost unbroken rule by the Liberal Democratic Party (LDP).
But even if the Democrats win a majority in the powerful lower house, they will need to form a coalition with two smaller allies because they lack control of the upper chamber. And an inconclusive outcome could spark a tug-of-war in which big parties woo members of other small parties and independents to try to form a coalition.
Following are some facts about the political parties that will be competing for seats in the lower house election.
LIBERAL DEMOCRATIC PARTY
The LDP has been in government either alone or in coalition almost continuously since 1955, when it was formed through a merger of conservative parties. The party won a landslide victory in the 2005 general election under popular leader Junichiro Koizumi and held 300 lower house seats ahead of the coming election. Prime Minister Taro Aso, 68, took over the reins in September 2008 after the sudden resignation of predecessor Yasuo Fukuda. LDP members span a spectrum from proponents of market-friendly reforms to fans of a bigger role for government in the economy and from advocates of a bolder global security role for Japan to relative doves.
DEMOCRATIC PARTY OF JAPAN
A mix of former LDP members, ex-socialists and conservative younger lawmakers, the Democratic Party was formed from smaller opposition groups in 1998 with the aim of wresting power from the long-ruling LDP. In 2003 it merged with Ichiro Ozawa's center-right Liberal Party. Voters fed up with the LDP gave opposition parties, led by the Democrats, control of parliament's upper house in 2007, enabling them to delay legislation and derail appointments. Like the LDP, the party is home to lawmakers with varied views on the economy and security. The party, led by Yukio Hatoyama after predecessor Ozawa quit to keep a fundraising scandal from scuppering his party's election chances, had 115 seats in the lower house.
Founded by members of a Buddhist sect, Soka Gakkai, Japan's third-largest political party is the junior ruling coalition partner. It tends to focus on economic policies for less well off citizens, and its pacifist leaning has led to clashes with the LDP over such matters as official visits to Yasukuni Shrine, which is seen by many in Asia as a symbol of the country's past militarism. The New Komeito held 31 seats in the lower house and is led by Akihiro Ota, 63.
JAPAN COMMUNIST PARTY
Formed in 1922, the Communist Party advocates breaking away from Japan's military alliance with the United States and more restrictions on large corporations. The party stresses welfare policies and is against revising the pacifist 1947 constitution. Led by Kazuo Shii, the party had nine seats in the lower house.
SOCIAL DEMOCRATIC PARTY
Once the main opposition force, the SDP lost many of its members to the Democrats in 1998 and had seven seats in the lower house. It is led by an outspoken former lawyer, Mizuho Fukushima, one of Japan's few female political leaders. The party emphasizes welfare policies and opposes revising the pacifist constitution. The Social Democrats are expected to join the Democrats in a coalition government if the LDP-led ruling bloc loses the poll.
PEOPLE'S NEW PARTY
The party was formed by conservative LDP lawmakers who in 2005 opposed Koizumi's plan to privatize the postal system. Along with two allies, it held four seats in the lower house. Party leaders have said they will cooperate with the Democrats in the election, but its members' conservative views also make the group a possible future partner for the LDP.
KAIKAKU (REFORM) CLUB
Made up of former independents and defectors from the Democrats, the party had only five members, with just one in the lower house. The group is widely thought to be ripe for a merger or cooperation with the LDP after the election.
NEW PARTY NIPPON
Reformist ex-governor and author Yasuo Tanaka is the party's only member of parliament. Elected to the upper house in 2007, Tanaka is seeking a lower house seat with the Democrats' backing.
The party was formed after the lower house was dissolved by a an ex-cabinet minister, Yoshimi Watanabe, who had left the LDP. Four party members held seats in the lower house. The pro-reform Watanabe has said he could cooperate with the Democrats.
HAPPINESS REALIZATION PARTY Formed in May 2009 by a Buddhist-based religious group, the Happiness Realization Party is endorsing 337 candidates, more than either major party, while also supporting some LDP candidates. In July, it backed 10 candidates in a Tokyo election, but won no seats. The party advocates dropping the pacifist Article 9 of Japan's constitution. (Reporting by Isabel Reynolds and Yoko Kubota)