Four AIADMK members were also declared winners in the RS polls from Tamil Nadu, with Dr V Maitreyan getting a record third term for any leader of his party.
The election of Kanimozhi and Raja were seen as indicators of fresh realignment of political parties ahead of the Lok Sabha polls in 2014.
An accused in the 2G spectrum case, Kanimozhi was elected on the basis of counting of votes done by elimination method which saw DMDK's AR Elangovan lose because of a rebellion by seven MLAs of his party who voted for the AIADMK.
Karunanidhi's bid to get a second Rajya Sabha term for his daughter saw him desperately turn to Congress chief Sonia Gandhi, three months after he had led the DMK out of the UPA after differences over the Sri Lankan Tamil imbroglio.
Though the DMK had only 23 votes, Kanimozhi got 31 votes after five Congress' MLAs voted in her favour along with two votes each from two smaller parties--Puthiya Thamizhagam and Manithaneya Munnetrak Katchi.