TAIPEI -- Taiwan's ruling Democratic Progressive Party faces dimming prospects in islandwide local elections on Saturday, threatening President Tsai Ing-wen's re-election bid and potentially affecting relations with Beijing.

The DPP and its leader Tsai are facing pressure from a surging wave of public support for Han Kuo-yu, the opposition Kuomintang's candidate for the mayoral election in the city of Kaohsiung, a traditional DPP stronghold. Han's phenomenal popularity is apparently translating into broader public support for the main opposition party.

If the DPP suffers a drubbing in the unified local polls, which are widely viewed as an effective referendum on the party and a dress rehearsal for the 2020 presidential election, Tsai's bid for re-election could be at risk.

In the regional elections, held every four years, voters choose the leaders of 22 cities and counties as well as local assembly members.

Until recently, the elections were expected to have no significant impact on the island's political landscape with both the DPP and the Kuomintang, or KMT, struggling to expand their support bases.

But Han's rise to political stardom has radically changed the outlook.

Kaohsiung mayoral candidate Han Kuo-yu has seen a meteoric rise in his popularity recently. © Reuters

The findings of the latest opinion poll by Taiwanese Public Opinion Foundation, released on Nov. 13, showed the KMT ahead of the DPP by nearly 12 points.

In the afternoon of Nov. 11, Han's ability to galvanize voters was on show in the southern city of Kaohsiung, where he was running for mayor.

When he appeared to speak to participants in a demonstration concerning an environmental issue, hundreds of supporters rushed toward him. Supporters started chanting "dang xuan" (election) in a loud chorus.

Many of the campaign promises Han has made so far are of doubtful feasibility. He has pledged, for instance, to invite a Disneyland to be built in the city and to increase the city's population to 5 million, from the current 2.77 million.

His popularity started its meteoric rise around October. An early November poll by commercial broadcaster TVBS showed him leading the DPP candidate Chen Chi-ma by 10 points.

The wave of public support for the 61-year-old Han has been splashed all over local media, which depict it as a social phenomenon.

Kaohsiung is a traditional bastion of the DPP, which has governed the city without interruption for two decades.

Initially, Han, a native of northern Taiwan and a relatively obscure political figure without strong backing from the party, was seen as a no-hope candidate. But he has turned his underdog position into a political advantage by adopting an audacious campaign strategy focused on casting him as an unusual reformist who can break through and upset the status quo.

Han has won wider sympathy among people dissatisfied with the ruling party by denying the status quo and calling for change. He maintains that Kaohsiung has turned into an old and poor city.

Chen, on the other hand, stresses the accomplishments of the DPP, and urges locals to believe in Kaohsiung. Chen pitches what he calls realistic economic policies.

Since Chen is an elite DPP member whose father served as a legislator, the campaign has underscored Han's resistance against the current political power elite.

By courting controversy, Han has built up a cultlike following in the online community. There have been many cases in which the social media accounts of people critical of the rising political star have been flooded with hundreds of thousands to over a million vitriolic and antagonistic comments by his apparent supporters.

The DPP has repeatedly accused China of interfering in the elections. Some wonder what drove Han's meteoric rise in such a short period of time: He has been mentioned three times more on the Internet than popular Taipei Mayor Ko Wen-Je, according to local media outlet New Bloom.

Meanwhile, the U.S.-China Economic and Security Review Commission, a bipartisan congressional panel, said on Nov. 14 that Beijing is carrying out extensive "united front" work to undermine Taiwan's democracy by spreading fake news through social media and other online platforms.

Despite the accusations of Chinese meddling, Han's popularity shows no signs of waning.

Lin Jia-rong, a 35-year-old employee at a local iron factory, is an ardent Han supporter. "I see hope in his battle to make the impossible possible," he said.

Lin laments the fact that many of his friends have migrated to Taipei and other northern parts of the island. He said he will vote for a candidate who can be expected to change the city's circumstances.

Han is attracting voters by tapping into a growing vein of discontent and disillusionment with the DPP. He argues that the upcoming election is a "vote of no-confidence" against the ruling party.

His spirited election campaign is posing an increasingly serious threat to the DPP.

The Tsai administration has pursued policy measures to improve working conditions and reform the public pension system. But it has been forced to water down the measures in the face of resistance from vested interests.

The political compromises the administration has made on these issues have deeply disappointed the party's key constituencies, especially young voters.

The Tsai administration has also suffered a series of bitter diplomatic defeats as five countries have severed their diplomatic relationships with Taiwan under pressure from China. It has failed to make any effective strategic responses to Beijing's diplomatic offensive to undermine the DPP's political standing.

The KMT is seeking to capitalize on Han's popularity to boost its electoral performance. KMT campaign cars have been roaming the streets of Taipei and other cities across the island, blaring speeches in support of Han. "I will vote for Han because this excellent candidate should not be allowed to lose," one line says.

The opposition party has replaced election posters for its candidates with new ones showing the candidates together with Han.

The party is avoiding mentioning its unpopular pro-China foreign policy and is focusing instead on promoting Han as its public face for the local elections.

The KMT's campaign strategy is apparently working, with voters critical of the DPP flocking to the opposition party.

The DPP is struggling to hold its own against the opposition party in several cities and counties, including the central city of Taichung. A defeat in Kaohsiung would deliver a heavy blow to Tsai's party leadership and jeopardize her grip on power.

In the previous local polls in 2014, the KMT suffered a resounding defeat as its pro-China policy turned off many Taiwanese voters, forcing party leader Ma Ying-jeou, who was then president, to resign to take responsibility.

The party also lost the presidential election in 2016 as it failed to recover from the electoral rout in 2014, allowing the DPP's Tsai to come to power.

The DPP is worried the same political dynamics could play out against it this time.

A party official admitted that the DPP is facing an unexpectedly tough battle but stresses that it can still turn the tables in the remaining time until election day on Saturday.