Gunmen sprayed bullets at a top redshirt hardliner on Wednesday in his hometown province of Udon Thani.
He was wounded in his right arm and leg and was rushed to a nearby hospital. His wife, Arporn Sarnkam, said Kwanchai is not in critical condition as the bullets did not hit important organs.
Initial investigation found that an AK-47 assault rifle was used from about 100 metres from the station's fence.
Kwanchai has played an active role in mobilising the supporters of the United Front for Democracy against Dictatorship (UDD) in the northeast.
The Khon Rak Udon group chairman has organised several movements and forums in the region to support the Feb 2 general election in opposition to the anti-government People’s Democratic Reform Committee (PDRC)'s demand for the resignation of the caretaker government and national reform before election.