Currently he is an AICC member of INC and general secretary of Kerala Pradesh Congress Committee.
His grandfather, Kaithavana Appukkuttan Pillai, was an active communist party worker, who participated in the Vallikunnam Meni Samaram, a political riot to save the labour rights of paddy field workers.
[citation needed] Mahesh started his political career as the unit president of Kerala Students Union (Students Organization of the Indian National Congress in Kerala) in Karunagappally model school.
Later, he joined for the higher studies in Political Science at Devaswom Board College, Sasthamcotta.
Mahesh held several positions like General Secretary of KSU Kollam district committee.