Access to college is critical for social mobility in China. Using a detailed college admission database that includes essentially all four-year public universities from 2005 to 2013, we demonstrate that Chinese universities preallocate more admission seats to provinces that happen to fall under the leadership of their alumni. Moreover, we demonstrate that the identified admission favoritism constitutes a political exchange between public universities and their powerful alumni in the sense that (a) universities and the connected provinces tend to sign formal partnership agreements; and (b) university leaders who sign formal partnership agreements receive indirect personal gains in terms of career advancement in the party-state bureaucracy. Our article provides causal evidence that social connections facilitate powerful government insiders' collusion and capture of public resources in a weak institutional environment.