The stage is set for a stiff fight between the Congress and its friend-turned-foe Telangana Rashtra Samiti.  The Election Commission announced on Tuesday that the bypoll in Karimnagar Lok Sabha seat in Andhra Pradesh will be held on December 4.

The seat was vacated by TRS chief K Chandrasekhara Rao, who quit the United Progressive Alliance, following differences over the Telangana issue.

Polling for Bobbili Lok Sabha seat, fallen vacant following the death of sitting Telugu Desam Party member, would also be held on the same day.

Rao, who had quit as Union labour minister a while ago, had already announced that he would contest from the seat and that the bypoll would be a 'referendum' on the Telangana issue.

He had challenged the Congress to face the electoral battle - "It will reflect the mood of the people of Telangana. Karimnagar will prove what is what."

The Congress had already named party MLA T Jeevan Reddy as its candidate for the seat to take on Rao. The TDP has also announced its nominee for the seat.

The TRS, which fought the 2004 general election in alliance with the Congress, withdrew support after not getting a commitment from Centre on carving out of a separate Telangana state from Andhra Pradesh.

Another highlight of the two Lok Sabha and 11 Assembly seats spread over ten states is polling in Chamundeshwari constituency in Karnataka, where a bypoll was necessitated with the resignation of former deputy chief minister Siddaramaiah after he joined Congress.

Siddaramaiah is a known detractor of former prime minister and Janata Dal (Secular) supremo H D Deve Gowda, whose son and Chief Minister H D Kumaraswamy has made the bypoll a prestige issue.