How will almost one billion people cast their vote in the world's biggest general election in India?

India's upcoming parliamentary election could see nearly one billion people cast their vote in what is the world's biggest general election.

The vote will decide whether Prime Minister Narendra Modi will stay in office for a rare third consecutive term. His Bharatiya Janata Party (BJP) remains hugely popular and is widely expected to secure another five years in power.

Almost 970 million Indians - more than 10% of the global population - are eligible to vote in the election. So how does such a big election work and what is at stake?

Who is on the ballot?

Modi has been travelling extensively across the country, holding road shows and rallies to campaign for the local BJP candidates, and is very much expected to hold onto power.

He is promising voters his party will make India a ‘developed nation’ by 2047.

The main challenger to the BJP and 73-year-old Modi is the Indian National Congress, which had governed the country for many of the 77 years since the country's independence.

After support for the party weakened, it formed a coalition with other opposition parties to form the Indian National Developmental Inclusive Alliance (INDIA).

The coalition has fielded a single primary candidate in most constituencies, but has been troubled by ideological differences and personality clashes, which means it hasn't yet chosen its prime ministerial candidate.

Leader of the Indian National Congress Rahul Ghandi has said his party has had its bank accounts frozen by the government's tax department, which has crippled their campaign ahead of the election.

Voters will elect 543 MPs to the Lok Sabha, the lower house of parliament, for a five-year term. To form a government a party needs 50% of the seats.

At the last election in 2019, the BJP won a large majority of 303 parliamentary seats, while the Congress party only secured 52 seats.

How does such a big election work?

Polling stations have had to be set up in the most remote areas of the country and voting will take place over the course of six weeks, from April 19 to June 1.

The polls will be held in seven phases and ballots cast at more than one million polling stations.

The winner of the long and logistically challenging election process will be announced on June 4

Each phase will last a single day with several constituencies across multiple states voting that day.

Some 15 million election workers will travel via road, boat, helicopter and even elephant to set up those polling stations, while candidates will march far and wide, accompanied by dancers, drummers and firecrackers, in order to attract votes.

Tashigang village, which is on the border with China, is the world's highest polling station at over 15,000 feet.

Around a quarter of the population cannot read so each party has its own symbol which appears on the ballot papers.

The BJP for example has a lotus flower, while the Congress Party's symbol is a raised open palm. The logos of other parties include a broom and a mango.

Hundreds of thousands of Indian nationals living in the UK are eligible to vote, but anybody wanting to do so, has to vote in person in India.

The winner will be announced on June 4.

What are the big issues?

Under Narendra Modi, India has become the world's fastest growing major economy but even as India's growth soars by some measures, the Modi government has struggled to generate enough jobs for young Indians, and instead has relied on welfare programmes like free food and housing to woo voters.

India has also become increasingly polarised with critics saying Modi's policies have transformed the country from a secular republic into a "Hindu-first" nation.

During his campaign for a second term, for example, Hindu nationalism featured more heavily.

Religious minorities have also suffered increasing numbers of attacks under Modi's reign, particularly the country's Muslims, of whom there are some 200 million.

Modi has also been accused of cracking down on independent media, with many watchdogs now categorising India as a “hybrid regime” that is neither a full democracy nor a full autocracy.

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