Definitely (based on Shia view) the ranking of Prophet Muhammad (peace be upon him and his family) is higher than Imam Ali (a.s.). But we believe that Imam Ali (peace be upon him) is the righteous successor of Prophet Muhammad. read more
Shias regard Ali as the first Imam and is considered, along with his descendants, to be one of the divinely appointed successors of Muhammad who are claimed by the Shia the only legitimate religious and political leaders of the Muslim community. read more