My friend in Bangkok estimated quarter million. No matter how much some people disagree with Thaksin, he's still the legitimate PM if there's still any sense of honoring democracy; he won two elections by popular votes but was ousted by force.
Some people mistakenly aliken Thaksin's TRT to Singapore's PAP. However, note that unlike in Singapore where the rich and powerful tend to side PAP, the poor people tend to side opposition. In Thaksin's case, it's reverse. The rich and powerful wanted him out and the poor and powerless supported him.
Poor Singaporeans complain ministers in power paying themselves millions and millions from taxpayers' money. Rich Singapore says it's OK, market rates. In Thailand, rich Thais accuse Thaksin of corruption and confiscate a huge chunk of his fortune, whereas the poor Thais accepted and defended Thaksin making his fortune the market way, not from the taxpayers but from the market in business. When in power, what did Thaksin do with taxpayers' money? He subsidised poor rural and farm regions heavily. The rich who paid most taxes are unhappy about it. They said Thaksin's using their money to buy votes. Thaksin abolished capital gains tax on M&A. Many rich Thais and companies jumped on it and made fortunes out of this law too. It's all debated and passed through in Thai Parliament. When Thaksin sold his Shin Corp to Temasek, they turn around and accuse him of abuse of power and evading tax. You go figure. Millions of Thais, however poor, have eyes and brains.