The results will also test BJP's strategy for forthcoming Assembly elections.
Early leads in 16 of the 32 assembly seats in eight states where votes for by-elections are being counted, show gains for the Congress. (
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The ruling BJP, which had been the party of choice in 18 of these assembly segments in the Lok Sabha elections earlier this year, is trailing in eight. The stakes are particularly high for the party, which had suffered reverses in a round of by-elections last month.
In sobering news for the BJP, the Congress is seen to be making gains in five seats in Gujarat, which the BJP had swept 26-0 in the May national elections. All nine Assembly seats in the state where by-elections were held were vacated by BJP legislators, who became MPs. The BJP is firmly leading in Maninagar, which was vacated by Prime Minister Narendra Modi.
Early trends in Uttar Pradesh too will worry the BJP; counting is being held for 11 assembly seats, 10 of them vacated by the BJP and one by an ally and one Lok Sabha seat vacated by Samajwadi Party chief Mulayam Singh Yadav. The BJP, while leading the total tally, is trailing in at least five assembly segments it won in May. At that time the party swept the 80 Lok Sabha seats in UP.
Mr Modi's BJP had won a spectacular mandate to take power at the Centre in the national elections this year. It hoped to carry the winning streak into by-elections held in August to 21 seats in key states like Bihar, Uttarakhand, Karnataka and Madhya Pradesh, but it performed much below expectation.
The key question that the August elections threw up is expected in some part to be answered today - is the "Modi wave" that the BJP says won it the national elections, still a factor?
Political rivals like the Congress, which partnered Nitish Kumar's Janata Dal United and Lalu Prasad's RJD to best the BJP in Bihar last month, say the "Modi wave" is over and will not apply to state elections.
For the BJP, today's results also test its strategy for Assembly elections in two important states next month - Maharashtra and Haryana. In both it hopes to extend big wins in the national elections to the assembly polls.
By-elections were held for 11 Assembly constituencies in UP, nine in Gujarat, four in Rajasthan, two in West Bengal, five in the Northeast and one each in Chhatisgarh and Andhra Pradesh. The Chhatiisgarh result will be declared later.
Elections were also held to three Lok Sabha seats - Vadodara in Gujarat, vacated by Prime Minister Narendra Modi, Mainpuri in Uttar Pradesh, vacated by Samajwadi Party chief Mulayam Singh Yadav and Medak in Telangana, the seat vacated by KC Chandrashekhar Rao after he became the new state's chief minister.