NEW DELHI — The world’s largest democratic elections will take place in seven phases starting on April 11 as Indian voters head to the polls to select their next government.

The much-anticipated announcement by India’s Election Commission marks the official start of the campaign, though politicians have been in election mode for months, holding rallies and rolling out measures to woo voters in this nation of 1.3 billion people.

Prime Minister Narendra Modi, leader of the Hindu nationalist Bharatiya Janata Party, is seeking reelection for another five-year term. Modi and his party remain favored to win the largest number of seats in India’s parliament.

On Sunday, India’s Election Commission said the first stage of the polls will take place on April 11, followed by six other stages concluding on May 19. The results will be announced on May 23.

With 900 million eligible voters, India’s election is a gargantuan undertaking. The poll is staggered into phases because of the security and logistical challenges involved in overseeing voting by so many people across such a diverse geography.

Modi won a landslide victory five years ago by tapping into the aspirations of India’s young population and promising corruption-free government after a series of scandals. He also represented a Hindu chauvinist strain of Indian politics.

Since Modi took office, violence by right-wing Hindu groups has increased, as has intimidation of journalists. He has presided over rapid economic growth and large investments in infrastructure such as roads and airports, but that expansion has not had a commensurate impact on job creation

Pratap Bhanu Mehta, a political scientist and vice-chancellor of Ashoka University, told a conference in Delhi last week that there were "high stakes" in the upcoming polls but "very low expectations." Unlike in 2014, voters are less likely to believe Modi can deliver on his promises to transform the country. 

Modi is pitted against a variety of opposition parties who could come together to unseat him. His main opponent is Rahul Gandhi, the leader of the Indian National Congress and a scion of the most famous dynasty in Indian politics, the Nehru-Gandhi clan. 

Recent weeks have shaken up the race. At the end of last year, Modi’s party suffered setbacks in state polls, suggesting voters were frustrated by his government’s inability to boost employment and increase farmer incomes.

But a massive suicide bombing in Indian-controlled Kashmir followed by a military confrontation with Pakistan has turned national security into a focal point. Modi has long touted his toughness on issues like terrorism and presented his opponents as vacillating and weak.

After a Pakistan-based terrorist group killed 40 Indian paramilitary officers in Kashmir on Feb. 14, Modi pledged to respond. Twelve days later, Indian fighter jets conducted a cross-border airstrike on an alleged terrorist training camp within Pakistan. Although there is no evidence that the strike caused casualties or damage, it marked a significant shift in the security dynamic between the two nuclear-armed neighbors.