On the face of it, of the three diferent elections taking place in Taiwan on Saturday, the parliamentary polls should be of the greatest significance.

The ruling Nationalist Party, or Kuomintang (KMT), has only a paper thin majority in the legislature and could well lose it - the first such setback in the party's history.

But elections to the Taiwanese legislature are being overshadowed by a contest which will take place at the same time in the capital, Taipei, for the job of city mayor.

The contest is seen by many as a clash of Taiwan's two biggest political personalities.

It pits the popular incumbent backed by the opposition Democratic Progressive Party (DPP), which supports an official declaration of Taiwanese independence, against a charismatic challenger from the KMT.

KMT mayoral candidate Ma Ying-jeou on the campaign trail

To Taiwan's political parties, the contest between the incumbent Taipei mayor, Chen Shui-bian, and his challenger, Ma Ying-jeou of the KMT, is not a fight over how the capital should be run - it is a struggle for the political future of the island as a whole.

To ordinary Taiwanese voters it is about which of the two enormously popular men has more personal pull.

In the four years since Mr Chen won the Taipei mayoralty he has built on his popularity not by banging drums for Taiwan's formal independence from China, but by focusing on practical problems such as Taipei's congested traffic and inadequate drainage.

Presidential ambitions

Opinion polls suggest he is running neck and neck with his rival, Ma Ying-jeou, a Harvard-educated former justice minister.

His image as principled fighter against corruption has won him many admirers - as have his youthful good looks earning him the nickname of ""Sonny Boy Ma".

Mr Chen is keen to play down the issue of independence

If Mr Chen wins, many believe he would be in a good position to enter the race for the presidency.

He knows that strident demands for independence for Taiwan would risk alienating voters, who have shown a strong preference for maintaining the island's status quo.

Mr Ma knows too that stressing his party's goal of eventual reunification with China would similarly risk deterring voters, most of whom can trace their ancestry back for many generations on the island and have no emotional bond with the mainland.

No matter how Mr Chen tries to play down the independence issue, however, some voters may still be swayed by the KMT's attempts to convince the electorate that victory for the DPP would exacerbate tensions with the mainland.

China has repeatedly refused to rule out the use of force against Taiwan should it declare independence.