Amidst international upheaval regarding missile threats from North Korea and domestic disputes over constitutional revision, Japanese citizens will head to the polls this Sunday to vote in the lower house election.

Prime Minister Shinzo Abe called the snap election last month with hopes of the ruling coalition of his Liberal Democratic Party and smaller Komeito Party retaining power. The main competition comes from the Party of Hope, created by Tokyo Gov. Yuriko Koike shortly after the election announcement, and the Constitutional Democratic Party of Japan.

Voters are focused primarily on each party's stance towards tax revenue use, reforms to Article 9 of the Constitution, and North Korea.

Reforms have shrunk the lower house by 10 seats to a postwar low of 465. Abe has said he will resign if his Liberal Democratic Party and its smaller coalition partner Komeito do not win an overall majority with a combined 233 seats.

Prime Minister Abe (R), who has been in power since 2012, has faced disapproval over his push to amend the war-renouncing Article 9 of the Japanese Constitution and two recent favoritism scandals. Upon announcing the election, Abe pledged to seek a fresh mandate for his tough stance against North Korea's nuclear and missile threats and on use of additional tax revenue from raising the consumption tax, but did not mention amending the constitution.

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Both the LDP and the Party of Hope are in favor of amending Article 9, with the LDP putting a greater emphasis on adding an explicit mention of the Self-Defense Forces, already having pushed security legislation through the Diet last year to expand the possibility of Japanese troops being deployed abroad.

The largest opposition party until recently, the Democratic Party led by Seiji Maehara (L), has split, and more than 100 of its conservative-leaning members have since joined the Party of Hope. Maehara and other DP senior members are running as independents, while Koike, a former LDP member, has opted to retain her status as governor and is not seeking a lower house seat.

The more liberal members of the Democratic Party formed the new Constitutional Democratic Party of Japan, led by former Chief Cabinet Secretary Yukio Edano.

The CDPJ argues that the security legislation introduced by the Abe administration is unconstitutional.

Voters get two ballots, voting for the party of their choice on the proportional representation ballot and specific candidate on their electoral district ballot.

Japan Communist Party leader Kazuo Shii, who opposes amendments to the Constitution, urges voters to cast ballots for his party as well as candidates endorsed by the united opposition front.

87-year-old former JCP chairman Tetsuzo Fuwa gave a stump speech in support of a candidate fielded by the party. He calls for Japan to facilitate a dialogue between the United States and North Korea under the war-renouncing Constitution.

Tadatomo Yoshida, head of the Social Democratic Party, says Japanese people have not felt the economic recovery under Abe's economic policies and vows to put an end to the Abe government that has "turned its back on people."

In the days leading up to the election a family learning and entertainment centerin Tokyo gave children the chance to "vote" for their preferred candidate with mock ballots.

Sunday's election is also the first lower house general election in which 18-year-olds can vote. Osaka high schooler Natsuki Nakagawa was both the first teen and the first person in Japan to vote when early voting began.

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