Rubuta ci gaba ga wannan sakin layi - Kaine ya sanar da goyon bayansa ga takarar shugabancin Barack Obama
a watan Fabrairun shekara ta 2007. An tabbatar da cewa amincewar Kaine ita ce ta farko daga wani jami'in da aka zaba a cikin jihar a waje da Illinois. Saboda Kaine ya kasance sanannen gwamnan jihar Kudancin, akwai hasashen kafofin watsa labarai cewa shi dan takarar mataimakin shugaban kasa ne. Obama ya goyi bayan Kaine a yakin neman zabensa na gwamna, yana cewa, "Tim Kaine yana da sakon alhakin kudi da karimci na ruhu. Irin wannan saƙo zai iya sayar da ko'ina". A ranar 28 ga Yuli, 2008, Politico ta ba da rahoton cewa Kaine ya kasance "mai matukar girma" a jerin sunayen Obama don mataimakin shugaban kasa, jerin sunayen da suka hada da Sanata Hillary Clinton na New York, Gwamna Kathleen Sebelius na Kansas, Sanata Evan Bayh na Indiana, da Sanata Joe Biden na Delaware. Daga karshe Obama ya zabi Biden. Daga baya an bayar da rahoton cewa Obama ya gaya wa Kaine, a cikin karya labarai a gare shi, "Kai ne zabi na zuciyata, amma Joe [Biden] ne zabi na kai". Daga baya Obama ya rubuta cewa a karshe ya rage zabin abokin takarar sa zuwa Kaine da Biden. Ya ce, "A lokacin, na fi kusa da Tim", amma Obama da masu ba shi shawara David Axelrod da David Plouffe sun yi mamakin ko masu jefa ƙuri'a za su yarda da tikitin "ƙwararrun lauyoyi biyu masu ƙarancin ƙuruciya, marasa ƙwarewa, da 'yanci na' yanci na' yanci" kuma Obama ya ji bambancin da ke tsakanin shi da Biden ya kasance ƙarfi, kuma cewa shekarun Biden da gogewa za su tabbatar da masu jefa ƙuri'a da ke damuwa cewa Obama ya yi ƙuruciya ya zama shugaban kasa.