BANGKOK Thailand -- Suppose they held an election and nobody came? Loosely speaking, that's what opponents of Prime Minister Thaksin Shinawatra hope will happen with the snap polls called by the Thai leader for next Sunday.

Complaining of alleged corruption, abuse of power and lack of moral leadership on the prime minister's part, his critics mostly from the educated urban elite have been trying to force him to step down.

Mass demonstrations have failed to shake Thaksin's will he vows not to bow to "mob rule."

Appeals to King Bhumibol Adulyadej, the country's revered 78-year-old monarch, to replace Thaksin have so far fizzled, as the palace adheres to its constitutional duty not to interfere in politics.

That leaves an unprecedented boycott of the upcoming polls by all three parliamentary opposition parties as the fallback plan to get Thaksin out.

It's a move that has been greeted warily by international election monitoring groups, who are concerned that Thai democracy, which has made clear if unsteady progress since casting off the yoke of military dictatorship three decades ago, may be faltering.

Why a boycott? Thaksin's Thai Rak Thai Party still enjoys strong support from the country's rural majority, who have benefited from his populist polices and who re-elected his party in a landslide last year. His opponents argue that he has bought his majority, through government handouts as well as the time-honored method of direct vote-buying.

"The polling booths are very important for democracy in Thailand; they are necessary but not sufficient" because Thaksin has corrupted the system, said Thitinan Pongsudhirak, a political scientist at Bangkok's Chulalongkorn University.

A boycott would not just be a statement of moral disapproval it could throw a spanner in the works. Many constituencies have only one candidate. Results in such districts are not valid if fewer than 20 percent of voters cast ballots for the lone candidate a possibility in areas where Thaksin's party has little support.

Loopholes may exist, but precedent suggests that the House of Representatives cannot legally convene unless all its 500 seats are filled. Should such a situation come to pass, the constitutional argument for royal intervention to replace Thaksin becomes much stronger.

However, foreign election experts contacted by The Associated Press by e-mail generally questioned the wisdom of a boycott.

Elizabeth Dugan, vice president for programs for the International Republican Institute, a U.S.-based democracy promotion and election monitoring group, said that "rarely has a situation presented itself that supports the effective use of an election boycott.

"In Thailand, citizens have the freedom to choose," she said. "But to wage a campaign to effectively boycott the election means having to do two difficult things: convince people that they should sit the election out and thereby forfeit or jeopardize future voting rights, and pour the resources into building awareness for their view that the elections in Thailand are manipulated.

"Those same resources, if poured into a campaign that instead provided a viable alternative in an election, would enable a much greater sense of democracy at work in Thailand."

The Sweden-based International Institute for Democracy and Electoral Assistance IDEA an intergovernmental organization that supports democracy, undertook a survey of six Asian election experts, who came to a consensus that "Election boycotts have no place in a functioning democracy; participation being at the heart of the democratic process."

"Boycotts could have a role to play in a democracy that is not functioning as it should be and where fair competition is impossible," said a summary of their views. "The problem lies in determining at what point conditions for a fair election are being violated to such an extent that a boycott is justifiable.

"Even if justifiable it should be considered as a last resort," they noted, warning that there is a danger that resorting to a boycott "can have a long-term and damaging effect on the democratic process."

One of its experts whose identities were kept anonymous by IDEA conceded Thitinan's point that vote buying, intimidation and other unfair promises often limit the way people understand and use the election process.

Elections are increasingly being regarded as standard practice in Southeast Asia, said another, with most countries in the region in a better position then a decade ago, "but there is widespread evidence of a political culture which favors strength and wealth."

Ultimately, said several experts, an election boycott alone is unlikely to force political change.

"Their impacts are often minimal and can be managed by the incumbent government unless the boycott is accompanied by other measures which hinder ability to govern or there is a minimum voter participation required," said IDEA's experts.

Ungovernability, noted one, could be fostered by violence or civil disobedience campaigns.

The bottom line, Rob Richie, executive director of the U.S. group FairVote said separately, is "whether those proposing a boycott truly have mass support, and, if they do, how violently the government will respond."