Thai protesters target "hearts and minds" of Bangkok

The common portrayal of the "red shirts" as a movement of uneducated, gullible bumpkins with a mob mentality deters others.

However, analysts said the support base for the campaign appeared to be diversifying.

"It's no longer rural versus urban and it has ceased to be the case for some time," said Charnvit Kasertsiri, a political historian.

"There is a lot of support for the reds even in Bangkok. The question is: Can they bring them out to the streets?"

Analysts say the "red shirts" need to be better organised and more united if they want an effective and prolonged rally.

Others point out that overthrowing a government is almost impossible in Thailand without intervention by the military or the judiciary, which brought down two Thaksin-allied governments.

(Additional reporting by Chalathip Thirasoonthrakul and Ploy Ten Kate; Editing by Martin Petty and Sugita Katyal)