He belongs to state X(Haryana) and lives in state Y(U.P) and challenges 3 term chief minister of the Z(New Delhi) and wins . Political hack it is , sounds like proxies and socks in use.
Delhi is not a state. Indian politicians have contested in constituencies they have not resided for a very long time. Kejriwal hasn't done something new here.
"A union territory, the political administration of the NCT of Delhi today more closely resembles that of a state of India, with its own legislature, high court and an executive council of ministers headed by a Chief Minister."