The Communist rule in both West Bengal and Kerala came to an end as the country's ruling Congress party and its allies emerged victorious, according to results of the 2011 Assembly elections.
In West Bengal, Mamata Banerjee's Trinamool Congress Party made history, on Friday, marking the end of a 34-year Communist rule.
Trinamool Congress-led combine was ahead in 212 seats with Mamata's party leading in 174 seats, well above the halfway mark of 147, and Congress in the rest.
"Today is a festival of democracy. The priority of the new government would be to restore people's democratic rights and provide good governance and impartial administration, free from politicisation," Banerjee told reporters.
"There will be end to autocracy and atrocities. This is the victory of people against years of oppression," she said.
Opponents had been trying to unseat the Bengali Communists since 1977.
Banerjee will call on Governor MK Narayanan at Raj Bhavan today evening to formally stake claim to form government in West Bengal.
Congress party meanwhile won in the state of Assam in the east, and narrowly defeated the ruling Communists in the southern state of Kerala.
The Congress-led UDF won by a margin of 72-68.
In Tamil Nadu, the electorate gave a verdict against DMK corruption, bringing back to power J Jayalalithaa who made a spectacular comeback after successive defeats in elections since 2004.
The counting in four states and one Union Territory began at 8 am on Friday. The elections last month involved four of India's 29 states, and about 140 million of its 675 million voters.