Why the Bihar election is too close to call

Pollsters admit the Bihar Assembly elections, with untested alliances and new caste coalitions, are too close to call.

The majority of opinion polls have projected a vote share of 40-43 per cent for both the Bharatiya Janata Party (BJP)-led National Democratic Alliance (NDA) and the grand alliance of the Janata Dal (United), Rashtriya Janata Dal and Congress. Only CNN-IBN and Zee News have projected clear winners, the former says the grand alliance and the latter the NDA.

KEY TAKEAWAYS

• NDA and grand alliance vote share in most polls varies between 40 and 43 per cent; three per cent swing either way can prove critical
• Opinion poll projections have been conducted (end Sept) five weeks from the results, a stray remark during campaigning could alter scenario  
• Bihar primarily rural population (70 %) where grand alliance has slight edge while NDA strongly placed in urban and semi-urban areas (30 %)

Yashwant Deshmukh of C Voter, which conducted the poll for Times Now, has predicted 117 seats for the NDA and 112 for the grand alliance.  "Seat projection is not part of the survey science. Converting vote share to seats is done through a mathematical formula," Deshmukh pointed out.

He admitted it was a close call, with as many as 72 seats where the margin was very narrow. Of these, the NDA is leading in 34 and the grand alliance is leading in 32.

What makes the Bihar polls distinct is the population profile of the state: 10 per cent urban, 20 per cent semi-urban and 70 per cent rural. "The BJP might win the urban and semi-urban seats with huge margins but lose the rural seats with very low margins, giving the grand alliance a lead in rural areas,"  Deshmukh said.

Psephologist Jai Mrug said in the previous Assembly polls in the state, 24 seats were decided by a margin of less than two per cent.

A swing of one per cent could change results in 24 seats this time as well, he added. With the standard margin of error for polls being three per cent, a two per cent swing could make all the difference, he pointed out.

The divergence in projections arises from factors like the period of polling, the projection mechanism, and the conversion of vote share to seat share. Sanjay Kumar of Lokniti-CSDS said polls were only indications. CSDS, unlike other agencies, states only the vote share: 42 per cent for the NDA and 38 per cent for the Grand Alliance.

"The election is very tight in Bihar and the difference in vote share between the winner and loser is as close as two to three per cent, so pollsters are finding it difficult to assess the result," Kumar added.