Workers put up a tent in the compound at Government House. Postcards sent to show support for caretaker Prime Minister Thaksin Shinawatra will be deposited in the boxes inside the tent.

Some bought batches of postcards to distribute to friends, colleagues and relatives. Others bought them to re-sell.

Thailand Post swiftly distributed 20 million postcards to 1,178 postal offices across the country following Thaksin's appeal for postcards to be sent to Government House.

The post office was swift to respond because it has been through this before, especially during football tournaments. During Euro 2000, 72 million postcards were sent and 152 million were sent during World Cup 2002.

Half of the 20 million postcards were distributed to postal offices in Bangkok and adjacent provinces, said Woodtipong Moleechad, executive vice-president of operations.

The 20 million postcards reserved for the campaign is equivalent to about one-third of the country's population. An extra 20 million postcards have been reserved in case the first batch runs out.

Woodtipong said 2 million postcards had been sold so far.

Thailand Post was ready to supply more postcards to any Bangkok post office within an hour and within a day for those elsewhere, he said.

Sales of postcards were highest in provinces in the North, especially Chiang Mai, and in the northeastern provinces of Buri Ram, Khon Kaen, Surin and Ubon Ratchathani.

Each postal office has between 200,000 and 300,000 postcards, but some have been supplied with as many as 500,000.

 Postal offices normally sell a few thousand postcards a day. Sales in southern provinces like Songkhla remained at normal rates, however.

"Maybe it is because Songklha's people support the Democrats," said Arun Suraksa, a postal officer there.

Chiang Mai Post Office yesterday sold 53,200 of the 400,000 postcards it had on hand, said its chief assistant Nurat Seansurin.

Most went in big lots, Nurat said. One person snapped up 30,000 and another took 20,000 postcards, he said. They sell for Bt2 apiece.

The office put up a sign asking people to send postcards jointly.

Some local administrations bought postcards to distribute to officials and villagers, an official said.

Four or five postcards were earmarked for each household, said the official who asked not to be named.

Numerous people bought 20 or 30 postcards each and some bought 100, postal workers said.

Khon Kaen Post Office plans to make rubber stamps with Government House's mailbox, PO Box 888, if it is inundated with postcards. It estimated it sold about 5,000 postcards yesterday compared to the usual 1,000 or so a day. It has a supply of 200,000 postcards for the campaign.

Niramon Insakul, 30, a resident of Khon Kaen's Ban Kud Kwang said 80 per cent of the villagers there support Thaksin and they began sending postcards on Wednesday. She said she bought 50 cards yesterday and planned to ask relatives to write supportive messages on them.

A tent and a big box were set up in the compound at Government House to contain the postcards.

Some have been given to Thaksin already.

Another box has been placed in front of the gate so people can deliver them in person.