Rubuta ci gaba don wannan sakin layi - An fara zabar Erdan a matsayin Knesset na 16 a zaben 2003. A lokacin wa'adinsa na farko a Knesset, Erdan ya kasance daya daga cikin masu adawa da ficewar shirin da aka yi daga Gaza.
wanda Firayim Minista Ariel Sharon na Likud ke jagoranta. A watan Nuwambar 2005, Bayan fuskantar adawa mai tsauri ga shirinsa, Sharon ya bar Likud tare da wasu MKs, kuma ya kirkiro wata sabuwar jam'iyya, Kadima. Erdan ya kasance a cikin Likud kuma bayan ya sami matsayi na huɗu a cikin zaben farko na jam'iyyar, ya riƙe kujerarsa a Knesset na 17 a zaɓen 2006 duk da faduwar Likud daga kujeru 40 zuwa 12 a Knesset. An sake zabar Erdan zuwa Knesset na 18 a shekarar 2009.