With one month to go before Taiwan's presidential election, polls show the ruling Democratic Progressive Party's candidate in the lead. But his closet rival from the largest opposition party, the Kuomintang, appears to be closing the gap.

Voters cast ballots on January 13 in the election held every four years to pick Taiwan's leader.

Vice President Lai Ching-te of the ruling Democratic Progressive Party, Kuomintang candidate New Taipei City Mayor Hou Yu-ih, and former Taipei Mayor Ko Wen-je of the second largest opposition Taiwan People's Party are running.

One of the most contentious issues is how to face China, which is intensifying its pressure on Taiwan.

The DPP's Lai rebuffs Beijing's claim that Taiwan is part of China, and is set to succeed President Tsai Ing-wen's policy of countering China's pressure by bolstering Taiwan's ties with the United States and other partners.

The Kuomintang's Hou argues that the Tsai administration is raising the chance of armed confrontation with China. He says he will work to lower the risk by deepening exchanges with Beijing.

The TPP's Ko is critical of both parties. He says the ruling Democratic Progressive Party is being disregarded by Beijing, while the Kuomintang is too submissive. He says he will start expanding exchanges with China in the fields of culture and economy.

Recent opinion polls show Lai leading the race with a support rate of over 30 percent. But Hou's rate is also climbing to around 30 percent. Ko places third in most polls, with a rate of under 20 percent.

The three contenders plan to hold large-scale rallies across Taiwan in order to shore up support.