Polling started in Israel in what is expected to be a close contest between Prime Minister Benjamin Netanyahu’s party and opposition leader Yitzhak Herzog.

Other than Netanyahu and Herzog, who is member of the Knesset (parliament) and chairman of the Labor Party, the other main candidates are Tzipi Livni, former justice minister, and Moshe Kahlon, former welfare and communications minister under Netanyahu.

According to authorities, up to 80 percent of Israel’s 5.9 million voters are expected to cast their ballots for the 20th Knesset that has become a referendum on Netanyahu’s six-year rule, the Times of Israel reported.

Most of the 10,372 polling stations opened at 7 a.m., and are slated to shut at 10 p.m. Some voting stations in rural communities, hospitals, and prisons opened an hour later.

Netanyahu on Monday said a Palestinian state would not be established on his watch, should he be re-elected.

He warned that any areas that came under Palestinian rule would subsequently become a Hamas stronghold.

He also vowed to increase construction in East Jerusalem, and said the city would never be divided.

Herzog, while visiting the Western Wall, one of the holiest Jewish sites, on Sunday pledged to “safeguard Jerusalem and its residents in actions, not just words, more than any other leader”.

In Israel, the prime minister heads the government and is the most powerful figure in Israeli politics. The term is for five years. Netanyahu is the ninth Israel prime minister and has held the position since March 31, 2009.