Exit polls in India predict Narendra Modi will be the country’s next prime minister

Hindu nationalist Narendra Modi is set to become India's next prime minister, exit polls showed on Monday, with his opposition party and its allies forecast to sweep to a parliamentary majority in the world's biggest ever election.

Indian elections are notoriously hard to call, however, due to the country's diverse electorate and a parliamentary system in which local candidates hold great sway. Pre-election opinion polls and post-voting exit polls both have a patchy record.

Modi, of the Bharatiya Janata Party (BJP), has electrified the lengthy contest with a media-savvy campaign that has hinged on vows to kickstart India's economy and create jobs.

Yet much depends on Modi winning enough seats to form a stable government that will allow him to push through his promised reforms.

India's staggered voting, spread over five weeks to reach the country's 815 million voters and move security forces around its varied terrain, ended at 6 p.m. local time on Monday. Results are due on May 16.

Could this be Congress' worst showing?

Research group C-Voter predicted 289 seats for the National Democratic Alliance headed by the BJP, with just 101 seats for the alliance led by the Congress party — which would be the ruling party's worst ever result.

Another poll, by Cicero for the India Today group, showed the NDA hitting between 261 and 283 seats. A majority of 272 is needed to form a government, although that is often achieved with outside support from regional parties.

Several national exit polls over-estimated the BJP's seat share in the last two general elections in 2004 and 2009. The ruling Congress party went on to form coalition governments on both occasions.

"We will only know if this 'Modi wave' has really happened after the election results," said Praveen Rai, a political analyst at the Delhi-based Centre for the Study of Developing Societies (CSDS), who published a report on exit polls last month. "It still might be more of a media wave, a manufactured wave."

Should Modi fall short of a majority when the results come in on May 16, he will need to strike a coalition deal with some of India's increasingly powerful regional parties.

Modi is a polarizing figure whose critics accuse him of turning a blind eye to religious riots in 2002 in the state of Gujarat, where he is chief minister. More than 1,000 people — most of them Muslims — were killed in the violence.

Modi denies the accusations and a Supreme Court inquiry found no evidence to prosecute him.

(Editing by Frank Jack Daniel and Mike Collett-White)