The Big Question: Why are Thai protesters giving blood, and when will the dispute be resolved?

Why are we asking this now?

In recent days, the streets of Bangkok have been swamped by tens of thousands of boisterous red-shirted protesters who say they are marching to save Thailand's democracy. As the so-called Red Shirts have filled the streets of the Thai capital they have been noisy but overwhelmingly peaceful. They have now started collecting blood – asking for 20 teaspoons from each demonstrator – and splashing it on the floor outside the Prime Minister's office. Health officials argue such a large amount of donated blood could be put to good use medically.

Who are the Red Shirts and what do they want?

They are overwhelmingly supporters of the ousted former prime minister Thaksin Shinawatra, who was forced from office by a military coup in 2006. Calling themselves the United Front for Democracy against Dictatorship (UDD), they had hoped to bring a million people to Bangkok to put pressure on the Prime Minister Abhisit Vejjajiva, forcing him to dissolve parliament and hold fresh elections. They argue that the Eton-educated Mr Abhisit was appointed as the result of a vote by parliament in 2008 and that he therefore lacks a popular mandate. Some have gone as far as to say he is the face of a military government in disguise.

What lies at the heart of the protest?

The Red Shirts say they are fighting the country's "elite" – senior members of the business community, army officers, royalists and urban conservatives who opposed Mr Thaksin and supported the coup that led to the installation of an interim military-backed government.

Many of them hail from the country's rural poor whose loyalty to Mr Thaksin is the result of populist policies which empowered a segment of Thai society that had traditionally been overlooked. Indeed, many of Mr Thaksin's opponents would like to see less democracy, with more members of parliament appointed rather than elected.

"The heart of the matter is the political role of powerful unelected institutions (like the military and the Privy Council) as obstacles to Thailand's democratisation," says Federico Ferrara, a professor at the National University of Singapore and author of the recently published Thailand Unhinged. "Ultimately, I believe that these institutions are destined to lose much of their power against an increasingly involved, sophisticated population."

Why is Mr Thaksin not in Thailand?

The former prime minister, who at one time owned Manchester City football club, went into exile after a series of corruption charges were brought against him and his wife. Last year he was convicted in absentia of corruption and sentenced to two years in jail and last month the country's highest court ordered that $1.4bn (£900m) of his assets be seized as a result of a series of illegal measures he took while in office that benefited businesses owned by his extended family.

Mr Thaksin, a former telecommunications tycoon who took a largely ceremonial job as economic adviser to Cambodia in order to rattle the Thai establishment, has always staunchly denied the corruption allegations. While he spends much of his time in Dubai, he remains the de facto head of the UDD and Puea Thai, a political party. It is understood that the man who won two landslide elections is currently somewhere in Europe, from where he has been regularly speaking to his supporters by video link.

Who are his opponents?

The coalition of interests opposed to the former prime minister is broad. The best-known, the Yellow Shirts, are distinct from his Red Shirt supporters as is a Thai green curry from a Thai red curry. Among the senior members of the Yellow Shirts were leading media figures and army officers. The movement has called itself the People's Alliance for Democracy (PAD), though the name is misleading. Many members of the movement believe democracy has been extended too far in Thailand and that many of Mr Thaksin's "yokel" supporters are ill-qualified to have a role in politics. They support the appointment of some members of the parliament. However, as Professor Duncan McCargo, of Leeds University, points out, the Yellow Shirts also formed their own political party last year. "They are sort of trying to have their cake and eat it," he says.

How much power do they have?

In short, a considerable amount. After democracy was restored in Thailand following the coup, another pro-Thaksin government was elected, headed by a former television chef, Samak Sundaravej. But in September 2008, Mr Samak was forced to stand down after it was found he had acted unconstitutionally by appearing on a cooking show while serving as prime minister. He was replaced by another ally of Mr Thaksin, Somchai Wongsawat, but after weeks of protests that saw the country's airports grind to a halt when they were over-run by thousands of demonstrators, he too stood down. The closing of the country's airports cost Thailand countless millions of dollars in much-needed foreign currency.

What is the role of Thailand's royal family?

Thailand's ageing and ailing monarch, King Bhumibol Adulyadej, holds a unique role within Thai society. Stringent "lese-majeste" prohibit the publication of anything considered defamatory or harmful of the royal family and have been used – claim some analysts – against those critical of the government. While the 82-year-old monarch has always claimed to play an apolitical role, there are many allegations that elements within the palace are close to the anti-Thaksin forces. Late in 2008, Queen Sirikit triggered considerable controversy when she attended the funeral of an anti-Thaksin demonstrator who had been killed in clashes with police.

What happens next?

In this instance, Mr Abhisit appears to have called the bluff of the demonstrators. Despite their theatrics with the blood, he appears firm in his rejection of their demand to dissolve parliament. Mr Ferrara believes it may even be in the interests of the Red Shirts to call it quits. "My bet is that the Reds will blink first and go home after a few days," he says. "In fact, they have little interest in escalating this situation much further in the very short term. After all, for all the hand-wringing about whether their numbers would be above or below expectations, they have successfully mobilised an unprecedentedly large group of provincial voters."

And in the longer term?

While Mr Thaksin is still interested in making a return to Thai politics – which he clearly is – there is unlikely to be any fast resolution to the crisis, which has been raging off and on since 2006. His supporters certainly remain convinced that if a fresh poll were called and if he were permitted to return to Thailand without being arrested, their champion would win a handsome victory.

Will Thailand's political crisis be resolved?

Yes...

* A groundswell of popular protest from those kept outside the system for generations will be hard to resist

* Mr Thaksin retains huge popularity and a large war chest that he is willing to spend to return to politics

* Any decision taken by the courts against Mr Thaksin can always be overturned

No...

* The current Prime Minister has powerful backers, including the conservative establishment

* The powerful royal family is said to oppose Mr Thaksin; their influence could be decisive

* There are too many vested interests in the country's political system for it to be liberalised