Two weeks ago, as the morning temperature in Bangkok unexpectedly dropped near 20 deg C, anti- government protester Panita Moumangsaosa sat comfortably outside a sports compound where registration of candidates for the Feb 2 election was taking place.
The clothing seller from the central Thai province of Chon Buri had slept overnight on the sidewalk to help her fellow protesters block political parties trying to register for the snap polls.
But the night was hardly rough, thanks to new tents and warm clothing handed out to them. "Rich people came and gave us blankets," she told The Straits Times.
The street protests aimed at unseating the caretaker government of Premier Yingluck Shinawatra are well into their third month, and showing few signs of letting up.
If anything, protesters aim to "shut down" Bangkok on January 13, leaving their main rally site in the inner city's Democracy Monument to move to several key intersections across the Thai capital.
They aim to root out all vestiges of the "Thaksin regime" of Yingluck's brother by delaying the February 2 election, and are demanding political reform under a "people's council" first.
The massive operation is costing anything from two million baht (US$30,239) to five million baht a day, reveals Akanat Promphan, the spokesman for protest organiser the People's Democratic Reform Committee (PDRC). That works out to well over 60 million baht so far.
Just who bankrolls it all? As with previous protests, the gaze has fallen on Thailand's corporate titans. Some of them are said to have been sidelined by the business networks of former premier Thaksin Shinawatra, and some are known for hedging their bets by supporting a variety of political factions.
Akanat denies their involvement. "There are a lot of rumours on the Internet that we receive donations from CP, from ThaiBev, from Red Bull, from wealthy people and from large corporations. None of that is true," he tells The Straits Times.
CP is the food and retail conglomerate Charoen Pokphand, which runs the 7-Eleven chain in the country. ThaiBev or Thai Beverage is a Singapore-listed beer company that was used by its founder Charoen Sirivadhanabhakdi to take over Fraser & Neave in 2012. And the Yoovidhya family behind the Red Bull energy drink is one of the richest families in the kingdom.
Akanat says the PDRC "rarely" gets sponsorship from big corporations, because "a lot of them had some relationship with the government".
Rather, he insists, it attracts donations from a broad spectrum of society. He adds that, in the beginning, protest leader Suthep Thaugsuban sold family land, mostly in southern Thailand, to start the campaign. Official records show the former deputy prime minister and senior member of the opposition Democrat Party declared 207 million baht worth of assets in 2012.
For weeks, Ratchadamnoen Avenue in inner Bangkok has been occupied by large stages, big screens and elaborate sound systems which broadcast nightly rallies to supporters. Cooks serve up piping hot noodles and rice for free distribution. Giant tents keep supporters cool in the midday sun. There is running water from modified fire hydrants nearby while water hoses are covered with tar to make mini speed bumps for blockaded roads.
Asean's second largest economy has witnessed periodic upheavals ever since Thaksin was deposed by a military coup in 2006 that followed mass protests. The tycoon had cut through longstanding patronage networks with policies like his 30-baht universal health-care scheme, and his foes include many in the old elite, royalist establishment as well as the urban middle class.
Back then, Thaksin's allies accused privy council chief Prem Tinsulanonda of masterminding the coup, though this was denied.
Still, the deep but discreet pockets that financed the old anti-Thaksin movements are said to be playing a part in this campaign to remove Yingluck.
During King Bhumibol Adulyadej's 86th birthday celebrations last month, protesters set off their own fireworks to rival those of a government event nearby. Weeks later, they set up fun fair stalls to ring in the New Year.
As the protest momentum grew, donations flowed in, says Akanat. Last month, after the Department of Special Investigation ordered the accounts of protest leaders frozen, supporters lined the streets to hand Suthep wads of baht. On December 22, he collected 10 million baht.
It helps that the average PDRC supporter is quite well off financially - an Asia Foundation survey of these supporters on Nov 30 found nearly one-third came from households earning more than 60,000 baht a month.
Analyst Kan Yuenyong from think-tank Siam Intelligence Unit says big business is almost always involved in large-scale protests like this, though also careful to keep out of view. "It's quite hard to estimate the money flow behind the scenes," he says.
Any open acknowledgement of political leanings has business implications in this deeply polarised climate. The family behind Boon Rawd Brewery, the maker of Singha beer, made its heiress Chitpas Bhirombhakdi, a protest leader, change her surname last month as pro-government red shirt supporters threatened to boycott its products. Such controversies, however, do not seem to have dried up the flow of money.
Akanat says: "This movement, in terms of funding, could go on, as long as it takes."
*US$1 = 33.07 baht