I muri i tana mahi hei kaiwhakahaere ā-rohe mō te Rōpū Manapori o Michigan i te pōtitanga ā-peresideni o te tau 2000, kātahi i te pakanga a John Kerry mō te peresideni i te tau 2004, ka uru atu a Simon ki te pakanga ā-peresideni a Barack Obama i te tau 2008
hei kaiwhakahaere tātaritanga, e noho ana i te tari matua o Chicago. Hei wāhanga o tēnei pakanga, i whakahaerehia e ia ngā pūranga raraunga mō te whanonga pōti me ngā manakohanga. Ko tana rautaki o te whaainga tika i whakawhiwhia ki te awhina ki te tautuhi i nga kaitono kaore i whakatau i taea e Obama te whakahoahoa. Whai muri i te pakanga, i tohua ia i te tau 2009 ki te mahi i roto i te Whakahaere Obama i te Tari Hauora me nga Ratonga Tangata, i reira i arotahi ai ia ki te whakahou hauora me te Medicare.