A roller coaster week in Taiwan politics ends with opposition still divided

Catch up quick: The ruling Democratic Progressive Party (DPP) candidate William Lai is polling far ahead of the other three candidates who will likely split the voter base of Taiwan's main opposition Kuomintang (KMT) party and virtually guarantee a DPP win on Jan. 13.

• "If the election were tomorrow, William Lai would win," Lev Nachman, an assistant professor at National Chengchi University whose expertise includes polling in Taiwan, told Axios.
• A Lai win would further solidify the U.S.-Taiwan relationship but enrage the Chinese government, which views Taiwan as its sovereign territory.
• Beijing would be likely to "use heightened military exercises, diplomatic pressure and economic sanctions as a way to exert pressure on a potential Lai presidency to set the terms of future cross-Strait interaction," Wen-Ti Sung, a nonresident fellow at the Atlantic Council's Global China Hub, said.

The big picture: Two parties, the KMT and the DPP, dominate Taiwanese politics, and presidential races are usually two-way races between candidates from those parties.

• This year, those candidates are Lai, who serves as vice president under current President Tsai Ing-wen, and the KMT candidate Hou You-yi, who is on leave as New Taipei City mayor.
• But two additional candidates have thrown their hat in the ring this year: Ko Wen-je, former Taipei mayor and chairman of the upstart Taiwan People's Party (TPP), and Foxconn founder Terry Gou.

What's happening: Late last week, the KMT's Hou and the TPP's Ko announced they had formed a coalition and would be running on a joint ticket — a matchup that could turn what would likely have been an easy win for Lai into one of Taiwan's most competitive elections in history.

• That's because the three non-DPP candidates are pulling mostly from the same voter base, greatly weakening the challenge to the ruling party.
• The most important issue for voters in Taiwan's presidential races is cross-Strait relations. Hou, Ko and Gou are all friendlier toward China than the DPP.
• China's Taiwan Affairs Office warned against what it called an "independence double act" after Hsiao Bi-khim, Taiwan's former representative to the U.S. who has advocated forcefully for Taiwan on the international stage, was named Lai's running mate last week.

But the coalition collapsed almost immediately, ending any possibility of a KMT-TPP joint ticket.

• It was perhaps the "most dramatic up and down" of any Taiwanese presidential race, Nachman said.
• Such a coalition was fundamentally flawed because Ko had founded his party explicitly as a rejection of the two-party system and had run as an outsider, an image with broad appeal among Taiwanese who similarly feel disillusioned with the two major parties.

What to watch: It's still possible the two outsider candidates might join forces, though neither have publicly stated an interest in doing so.

• Ko and Gou have a lot in common, said Sung, and their resources are complementary. In a potential joint ticket, "Terry Guo would provide the finance, while Ko Wen-je has much more of a party machinery ready to go," Sung added.
• "If they were to form an alliance, that would seem to make sense."

Editor's note: This story has been corrected to reflect that Hou You-yi is still the mayor of New Taipei City but is on leave while he runs for president, and to remove a reference to him as a medical doctor, which he is not.