Thaksin Shinawatra's Thai Rak Thai party won the election held two days ago. The result was hardly unexpected, as the Democrats and other opposition parties boycotted the election. In fact, TRT was unopposed in many northern constituencies (TRT's heartland), and many voters in Bangkok and the south (the Democrat's stronghold) abstained as there were no Democrat candidates.
There have been street protests by monarchists in Bangkok for the past few months, eventually leading Thaksin to dissolve parliament in February. The protests started after Thaksin sold a 48% stake in his Shin Corp. business to Singaporean company Temasek. Thaksin's government had increased the legal limit on foreign ownership of national assets to enable the Shin sale, and changed the tax code to avoid paying any tax on the deal, a blatant manipulation of the law for personal gain.
Thaksin has announced that despite winning a majority, he will not accept the position of Prime Minister. He had earlier joked that he would quit "If His Majesty whispers in my ear", a remark that further angered his opponents as it showed an apparent lack of reverence towards the King.