Polling has opened in India's multi-phase general elections as millions will vote in 91 constituencies across 20 states in the first phase of the polls, reports Aljazeera.
Polls are also being held in the militancy-wracked Jammu and Kashmir state as well as in Chhattisgarh, which is plagued by a left-wing Maoist insurgency.
India's gargantuan election, the biggest in history, sees Prime Minister Narendra Modi seeking a second term from the South Asian behemoth's 900 million voters.
Opinion polls put Modi, 68, as the favourite but he faces a tough challenge from not one but two scions of India's storied Nehru-Gandhi dynasty attempting to capitalise on his poor record on jobs and rural poverty.
Because of the vastness of India, the election will be held in seven phases, from the tea plantations of Darjeeling to the slums of Mumbai to the tropical Andaman Islands, and everywhere in between.
The seven-phase elections will conclude on May 19. Results will be announced on May 23.
Al Jazeera's Nadim Asrar, reporting from Noida, said voters were turning out slowly.
"There's a slow but steady trickling of voters at a polling booth in a middle-class neighbourhood of Noida. Security personnel guard the gates of a community centre where the polling is being conducted."
Security forces are on high alert due to the perennial danger of violence, with five people, including a local politician, killed in an ambush by suspected Maoist rebels this week.
More than 11 million election officials, including security forces, will be deployed across more than one million polling stations to "conduct the biggest management event of any kind".
Modi and his right-wing Bharatiya Janata Party (BJP) swept to power in 2014 with their famous promise of "achhe din" (good days), becoming the first party to win an absolute majority in 30 years.
"Nationalism is our inspiration and inclusion and good governance is our mantra," Modi, whose stern bearded face stares out from ubiquitous posters, said at the launch of his manifesto.
Rahul Gandhi, 48, hoping to become the latest prime minister from his dynasty - and aided by sister Priyanka - has accused Modi of causing a "national disaster".
Gandhi's Congress party has profited from voter dissatisfaction, winning three key state elections in December, chipping into Modi's core support base in the Hindi-speaking heartland of northern India.
The alliance led by Modi's BJP is poised to win a narrow majority of 273 of the 543 seats at stake, an average of four opinion polls showed.
But opinion polls are notoriously unreliable in India and much will depend on the BJP's performance in several key states, in particular Uttar Pradesh and West Bengal.
"It's difficult to predict," said Parsa Venkateshwar Rao, a veteran journalist and political commentator.
"It reminds me of 2004 when (premier Atal Bihari) Vajpayee and the BJP lost when everyone expected them to win," he told AFP news agency.