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Veiled women wait to get their voting slip from an officer at a polling station during the state assembly election in Hapur, in the central state of Uttar Pradesh, India, February 11, 2017. REUTERS/Adnan Abidi

Akhilesh Yadav (L), Samajwadi Party (SP) President and Chief Minister of the northern state of Uttar Pradesh, and Rahul Gandhi, Vice-President of India's main opposition Congress Party, pose for the media as they release a common minimum programme at a joint news conference in Lucknow, India February 11, 2017. REUTERS/Pawan Kumar

The Samajwadi Party, which runs Bihar and is led by 43-year-old Chief Minister Akhilesh Yadav, won a majority in the last state election, in 2012, with just 29 percent of the vote.

Yadav has formed an alliance with Rahul Gandhi of the Congress party that, polls show, will be tough to beat.

Ranking third, Mayawati, who ran the state from 2007 to 2012 and whose Bahujan Samaj Party draws its support from communities on the bottom rung of India's ancient caste hierarchy.

She has fielded a big crop of candidates from the Muslim minority that makes up 19 percent of the state's electorate. Polls show most Muslims siding with the ruling Samajwadi Party-Congress alliance, however.

Results from Uttar Pradesh, along with Punjab, Goa, Uttarakhand and Manipur, are due on March 11.