All followers of Adhi Sankarar are smarthas. Namboodhiris in Kerala, Iyers in Tamilnadu, Iyer/Sastri/Sharma in Andhra and Hoysila brahmins in Karnataka are smarthas only. I don't have much of idea about other parts of the country.
Paramacharya is a Hoysila brahmin of Karnataka origin.
Present Junior Acharya of Kanchi mutt is of Telugu origin
Prsent Sringeri Acharya is of Telugu origin.
Adhi Sankara has formed mutts in Puri, Dwaraka and Jythimutt in the east, west and northern parts of India and hence will have followers there also.
All the best