Taiwan's first lady has been cleared by prosecutors of alleged involvement in a scandal, but that has failed to weaken the movement to oust her husband, Chen Shui-bian, from the presidency. As a round-the-island protest to demand his resignation continues, the campaign is leaving an indelible mark on Taiwan's political scene. The campaign led by Shih Ming-teh has succeeded in transcending a traditional fault line that has defined Taiwanese politics for decades - the two-way split between the Kuomintang and the Democratic Progressive Party. The major issue that divides them is reunification with the mainland. The Kuomintang, whose defining colour is blue, is in favour of eventual reunification, while the green-coded DPP is against. Other smaller parties have emerged since then, but the fundamental division between the so-called pan-blue and pan-green camps has persisted. For the first time in Taiwan's political history, the 'red tide' unleashed by Mr Shih's call for clean government has straddled that traditional divide. Although the campaign's key organisers are disillusioned DPP members, most protesters are believed to be Kuomintang supporters. What is uncertain is whether the 'red tide' will coalesce into a political force capable of redefining the island's political landscape. The early signs are not promising, and that is a pity. The mass movement lacks the support of business conglomerates whose financial resources are critical to the operation of any political groups. Instead, it is being funded by public contributions from millions of donors. Mr Shih is a former chairman of the DPP and has ruled out forming a new political party. He has made it clear that his aim is to reaffirm Taiwan's core values and restore the DPP's reform image. It is difficult to predict how the campaign will unwind. Much will depend on the progress of investigations into other alleged irregularities committed by the president and his aides in using - or misusing - a fund for clandestine diplomatic activities. Mr Shih said the campaign would not end until Mr Chen resigned. But the DPP is unlikely to dump a president it has laboured so hard to install, unless investigators unearth irrefutable evidence of fraud by the presidency. If Mr Shih sticks to his pledge, there is a chance he will try to sustain his campaign until Mr Chen's term ends in 2008, with unpredictable consequences for its participants and Taiwan's nascent democracy. Mobilising the masses to unseat an elected president is undemocratic and unwise. Taiwan's democracy is weak, but these are not the means by which to bring about change. Mr Shih has struck a responsive chord with the Taiwanese people. He should, however, use his charisma to channel the public's enthusiasm for strengthening the institutions of democracy. Taiwan's democracy would suffer if Mr Chen was forced to resign by a form of mob rule. The Kuomintang has filed another recall motion that, if passed by the legislature, would require a referendum to be held to decide whether Mr Chen would stay. With a vote due to be taken in mid-October, Mr Shih should switch his campaign's objective to pressuring DPP legislators to support the motion. Failing that, he should try to direct the 'red tide' to target every politician of dubious character, whether from the pan-blue or pan-green camp, at the next election. For a long time to come, reunification with the mainland is likely to remain a dominant issue in Taiwanese politics. But voters should not allow that to override other major considerations, such as whether politicians and their parties are clean. As a politician, Mr Shih has few equals in Taiwan. But others who are able to ride on the public's aspirations for corruption-free government, aroused by his campaign, could have a bright future. However remote the prospect may seem, Taiwan would benefit from the emergence of a new political party - one free of the established parties' troubled past and with a pragmatic platform to root out graft.