Why the Thai Protest Is Losing Steam BANGKOK - Even as demonstrators were spreading across Bangkok this week, they were losing ground with a constituency whose support they badly need: the urban middle class. The protesters - themselves mainly from white-collar backgrounds - are intent on bringing down Prime Minister Yingluck Shinawatra. She was elected in 2011 on promises to revive the popular policies of her elder brother, Thaksin, who was prime minister from 2001 until he was ousted in 2006. But her opponents are claiming that the government is corrupt, and those policies ruinous. Meanwhile, the threat of violence is growing: Dozens of people were wounded on Friday when an explosion hit antigovernment demonstrators marching through the city. The government has tried to mitigate the crisis by calling an early election, for Feb. 2 - even though that will not improve its legitimacy. The Democrat Party has said it will boycott the vote; it wants nothing less than Ms. Yingluck's departure. This was what the protest leader, Suthep Thaugsuban, was hoping to achieve when he called, earlier this month, for vast protests to try to shut down Bangkok. But the demonstrations have threatened to become so disruptive to everyday life and the economy that even people who support the opposition are being turned off it. This is a significant shift, for it presents Thailand with an 11th-hour opportunity to find a peaceful resolution to the deadlock. The standoff is the latest round in a conflict that began in 2006 when the army toppled Mr. Thaksin on grounds of abusing power and offending the monarchy. The next election restored a pro-Thaksin government, sparking mass protests by the so-called Yellow Shirts; more instability ensued. After yet another election in 2011, won decisively by Ms. Yingluck, opponents of the Shinawatras have repeatedly tried to stir up public opposition and vainly appealed to the generals and the palace to throw her government out. The crisis exploded in late October when the government clumsily attempted to pass an amnesty bill that would have allowed Mr. Thaksin to return to Thailand and even possibly reclaim his seized assets. There was an immediate outburst of anger, which then matured into more general discontent with the politicians in power. At first, in the fall, the demonstrations were brilliantly devised for urban white-collar workers: Messages on social media invited flash mobs to convene over the lunch break at intersections served by mass transit and on Sundays for major gatherings. Since then, the protesters have marched around the city along the routes that the so-called Red Shirts backing Mr. Thaksin had followed in 2010, when they were demanding a new election. Yet Mr. Suthep and leaders of the protest movement have struggled to keep the demonstrations going on a large scale: Their core supporters need to keep office hours. Organizers have tried to make up by bussing in supporters from the Democrats" stronghold in southern Thailand and recruiting students, especially from vocational schools, which are notorious for brawls. These recruits have been involved in several clashes that have left eight dead. The protest leaders have proposed no attractive alternative to the Yingluck government - just the vague notion of creating a "people's council" that would set up an interim government and oversee a reform agenda (still to be determined). And their rhetoric has grown increasingly shrill. A varied roster of speakers - politicians, doctors, high-society women - have taken turns hounding the whole Shinawatra clan, sometimes with lewd, sexist and ultranationalist abuse. After Thailand's leading English-language daily, The Bangkok Post, called the demonstrators its "people of the year," the paper's editorial writers began lambasting Mr. Suthep for disrupting the city, provoking violence and wrecking the national economy. Other media outlets also have cooled down. Huge billboards have appeared demanding "Stop Suthep Shutting Down the Country and Damaging the Economy." Citizens" groups have begun holding candlelit vigils calling for peace. A coalition of business associations has desperately tried to broker a compromise to stem economic damage. Parts of the urban middle class have cooled on Mr. Suthep's plans to oust the government by paralyzing their city. Even if they still support the objective, they have come to question the method. This is a chance to get beyond the current political impasse. The Democrats strongly supported the protests at first, but have moved quietly into the background over recent weeks. Dissenting voices in the party have pressed its leaders to accept the government's recent proposals to set up a process for reform and to drop its boycott of the election. The Election Commission has proposed delaying the voting by several weeks so that more candidates can be registered - demonstrators have blocked registration in several constituencies - and the Democrat Party can reconsider its boycott. So far, the party is still refusing to participate. Unless the party changes its position, it risks losing even more support among the urban middle class. Without some such compromise, Thailand will slide toward an election that cannot resolve the crisis and may be marked by violence, perhaps even a coup. Pasuk Phongpaichit, a professor emeritus of political economy at Chulalongkorn University, and Chris Baker are the authors of "Thaksin: The Business of Politics in Thailand."