By Bertil Lintner CHIANG MAI - A mass movement is spreading across Myanmar on a scale not seen since tens of thousands of Buddhist monks led anti-government demonstrations in 2007 and the massive nationwide pro-democracy uprising against the old military regime in 1988. This time the mobilizing force is a by-election contested by pro-democracy leader Aung San Suu Kyi and her National League for Democracy party to fill 48 seats in parliamentary bodies currently dominated by military aligned representatives.