Early state election results in the central state of Madhya Pradesh show a nail-biting contest between India's ruling BJP and opposition Congress.
The leads show a late comeback for the BJP in the central state. Early results showed a clear lead for the Congress.
However, Congress is leading in Rajasthan and Chhattisgarh, which were previous BJP strongholds.
Correspondents say the losses are a predictable and likely temporary backlash against incumbent parties.
India will hold nation-wide parliamentary elections early in 2019.
Election results are also being declared for the southern state of Telangana and the northeastern state of Mizoram.
Regional parties - the Telangana Rashtra Samiti (TRS) and the Mizo National Front (MNF) - are leading in these states.
The Congress was widely expected to win in the northern state of Rajasthan, while the central state of Madhya Pradesh was always seen as a close contest between the two parties.
But early results in the central state of Chhattisgarh, where the Congress is ahead by a wide margin, have been the most surprising.
BBC Hindi's Nitin Srivastava who is in Rajasthan, has been posting photos of the starkly different atmospheres at the BJP and Congress party offices in the state.