The huge crowds at opposition leader Tejashwi Yadav's rallies are "natural" and "happened even during his father Lalu Yadav's rallies" but the picture will change when Prime Minister Narendra Modi starts campaigning in Bihar for the election starting next week, top BJP sources said today. With a week to go before the polls, images of massive crowds at the rallies of Tejashwi Yadav, the Rashtriya Janata Dal (RJD) chief and the opposition mahagatbandhan's chief ministerial face, are believed to have caused some trepidation among Chief Minister Nitish Kumar's supporters.