Who is behind the successful trust vote

UPA won the trust vote by a comparatively higher margin but who helped them, interestingly it is the cross votes which played an important role and bulk of them from BJP. Why did not BJP try to convince their rebellions before the trust vote? It was all open in the media especially of the Karnataka MPs would abstain or vote for UPA. Why were there no serious efforts to make them vote against the government? I think NDA got what it wanted by waving the cash in the parliament which in turn also sidelined the much hyped Mayawathi's PM image in matter of few hours and gave BJP a central stage ......