Priyanka Gandhi Vadra, a leader of India's main opposition Congress party and sister of the party president Rahul Gandhi, prays on the banks of the river Ganges during an election campaign in Varanasi, India, March 20, 2019.

India's Prime Minister Narendra Modi gestures as he addresses an election campaign rally in Meerut in the northern Indian state of Uttar Pradesh, India, March 28, 2019.

Priyanka Gandhi Vadra, a leader of India's main opposition Congress party and sister of the party president Rahul Gandhi, waves to her supporters after addressing an election campaign meeting in Ayodhya, India, March 29, 2019.

Priyanka Gandhi Vadra, a leader of India's main opposition Congress party, waves as she arrives to address her party's supporters during a public meeting in Gandhinagar, Gujarat, India, March 12, 2019.

Rahul Gandhi, President of India's main opposition Congress party, addresses his party's supporters during a public meeting in Gandhinagar, Gujarat, India, March 12, 2019.

A worker displays T-shirts with images of (L-R) Chief Minister of West Bengal state Mamata Banerjee, Prime Minister Narendra Modi, India's main opposition Congress party Chief Rahul Gandhi and logo of Communist Party of India (Marxist) CPI (M), for sale inside a shop at a market ahead of India's general election, in Kolkata, India, March 26, 2019.

Demonstrators shout slogans during a protest rally, organised by Trade Union Centre of India, to demand implementation of national minimum wage an end to contract labour, in Ahmedabad, India, March 28, 2019.

A supporter holds a mask of Amit Shah, President of India's ruling Bharatiya Janata Party (BJP), during a road show by Shah before filing his nomination papers for the general election, in Ahmedabad, India, March 30, 2019.

Rahul Gandhi, President of India's main opposition Congress party, looks up before releasing his party's election manifesto for the April/May general election in New Delhi, India, April 2, 2019.

Workers sell masks of India’s Prime Minister Narendra Modi, and mugs and T-shirts featuring India’s ruling Bharatiya Janata Party (BJP) outside the venue of an election rally by BJP in Meerut in the northern Indian state of Uttar Pradesh, India, March 28, 2019.

A woman walks past a wall painted with the election symbol of India's ruling Bharatiya Janata Party (BJP) in an alley at a residential area in Kolkata, India, March 22, 2019. Picture taken March 22, 2019.

Amit Shah (C), President of India's ruling Bharatiya Janata Party (BJP), waves to his supporters during a road show before filing his nomination papers for the general election, in Ahmedabad, India, March 30, 2019.

Priyanka Gandhi Vadra, a leader of India's main opposition Congress party and sister of the party president Rahul Gandhi, prays on the banks of the river Ganges during an election campaign in Varanasi, India, March 20, 2019.

Supporters of India's ruling Bharatiya Janata Party (BJP) waves towards Prime Minister Narendra Modi during an election campaign rally in Meerut in the northern Indian state of Uttar Pradesh, India, March 28, 2019.

Priyanka Gandhi Vadra, a leader of India's main opposition Congress party and sister of the party president Rahul Gandhi, is garlanded by her party members after she arrives to address an election campaign meeting in Ayodhya, India, March 29, 2019.

A worker pulls a roll of flags of India's main opposition Congress party kept for drying at a flag manufacturing factory, ahead of the 2019 general elections, in Ahmedabad, India, March 13, 2019.

Rajiv Mondal, 36, a Trinamool Congress (TMC) party supporter shows a torn banner after his party office was burnt at Kanthi in Purba Medinipur district, India, February 6, 2019. Picture taken February 6, 2019.

Shivraj Singh Chouhan, Vice President of India's ruling Bharatiya Janata Party (BJP) sits at a roadside restaurant after attending a rally at Kolaghat in Purba Medinipur district, India, February 6, 2019. Picture taken February 6, 2019.

A supporter of India's ruling Bharatiya Janata Party (BJP) wearing a mask of Prime Minister Narendra Modi checks his mobile phone as he attends an election campaign rally being addressed by Modi in Meerut in the northern Indian state of Uttar Pradesh, India, March 28, 2019.

A taxi drives past a poster of Mamata Banerjee, Chief Minister of West Bengal state, in Kolkata, India, February 9, 2019. Picture taken February 9, 2019.

India's Prime Minister Narendra Modi is presented a "Japi" (a traditional hat of Assam) and a traditional brass metal pot by party members during an election campaign rally at Moran town in the northeastern state of Assam, India, March 30, 2019.

Priyanka Gandhi Vadra (C), a leader of India's main opposition Congress party and sister of the party president Rahul Gandhi, gestures as she speaks with women during an election campaign meeting in Ayodhya, India, March 29, 2019.