More than 900 candidates have registered for next month's parliamentary elections, South Korea's election watchdog said.

A total of 944 candidates -- 844 men and 100 women -- are set to compete for the 253 seats up for grabs on April 13.

The competition rate is 3.7 to one, compared with 4.84 to one in the 2004 parliamentary elections.

The remaining 47 seats will be allocated to political parties according to the numbers of votes that they receive overall under proportional representation, the National Election Commission said late Friday.

The election watchdog also said a total of 25 political parties participated in the elections, although three major parties -- the ruling Saenuri Party, the main opposition Minjoo Party and the splinter People's Party -- currently hold most of the seats in the National Assembly.

Other parties have little, if any, influence in local politics, as some of them were formed just one month ahead of the parliamentary elections.

Ten candidates are set to face off in the Jongno Ward of central Seoul, making it the most heated race in the elections.

Jongno Ward -- home to Cheong Wa Dae, South Korea's presidential office and the government complex building -- is a crucial electoral district, as it carries political significance for candidates and their political parties.

A recent poll showed that Oh Se-hoon of the ruling Saenuri Party is a frontrunner in Jongno Ward. He is set to face off against Chung Sye-kyun of the main opposition Minjoo Party, who currently represents Jongno Ward in the National Assembly.

Oh resigned from the Seoul mayorship in 2011 after he failed to block an opposition-led free school lunch program in the city's first-ever referendum.

In a country where about one-fifth of its 50 million people live in the capital city, the Seoul mayorship often serves as a key stepping stone for the country's president. Former President Lee Myung-bak served as Seoul mayor in the early 2000s before being elected president.

Meanwhile, Lee Koon-hyon, a candidate of the ruling party, was elected even before the elections began, as he is the only candidate running in the country's southeastern port city of Tongyeong.

In Seoul, nine candidates -- some of them from minor parties or independents -- have paid no taxes over the past five years, while

Ahn Cheol-soo, head of the splinter People's Party, paid 20.7 billion won ($17.7 million) in taxes over the same period.

The election watchdog also said 82 out of the 205 candidates in Seoul have criminal records, including drunk driving, theft and violation of the country's National Security Law.

The election watchdog said the richest candidate is Kim Byoung-gwan of the main opposition Minjoo Party.

Kim's wealth is valued at 263.7 billion won. Kim is the largest shareholder of South Korea's online game developer Webzen Inc.

The average net worth of the candidates is 2.5 billion won.

(Yonhap)