Rivkin akashanda semumiriri weCalifornia mukuru weSenator John Kerry paDemocratic National Convention muna 2004 naBarack Obama paDemocratic National Convention muna 2008. Rivkin akanga ari California mari co-chigaro nokuda Obama kuti 2008 mushandirapamwe wenyika
uye mumwe wevanonyanya kuunganidza mari yake.