The Election Commission on Thursday announced that elections for seven Rajya Sabha seats and a bypoll to the Bihar Legislative Council would be held on October 4.

The Rajya Sabha polls will not significantly alter the balance of power in the Upper House.

The polls declared on Thursday are for a seat each from Bengal, Assam, Maharashtra, Madhya Pradesh and Puducherry and two seats from Tamil Nadu. The results will be declared on October 4 itself.

The Bengal seat fell vacant with the resignation of Manas Ranjan Bhunia who successfully contested the recent Assembly elections.

Of the 233 seats occupied in the 245-member Rajya Sabha, the NDA has 116 MPs but is able to pass most bills with the support of or abstentions by parties such as the Biju Janata Dal, YSR Congress and the Telangana Rashtra Samithi.

After the polls, the NDA is expected to increase its tally to 119.

The EC is likely to declare polls for a vacant Rajya Sabha seat from Bihar after the by-election for a seat that fell vacant after the death of Janata Dal United MLC Tanveer Akhtar.

Of the seven seats, three are expected to go to the NDA — while the Assam and Madhya Pradesh berths will be filled up by the BJP, the Puducherry seat will have a claimant from either the BJP or its ally All India Namathu Rajyam Congress (AINRC).

Sources said the BJP is likely to field former chief minister Sarbananda Sonowal from Assam.

The Congress is expected to get the Maharashtra seat and field former Union minister Mukul Wasnik. Trinamul has the numbers to fill up the Bengal seat, likely to go to Congress defector from Assam, Sushmita Dev.