Varanasi, India (CNN)The River Ganges, or the Ganga to Indians, is one of Hinduism's most sacred waterways. Considered the personification of goddess Ganga, it is worshiped by millions of the faithful.
For Modi, India's marathon election ends where it all began
It flows through Varanasi, one of Hinduism's holiest sites and among the oldest continuously inhabited cities in the world. Millions of pilgrims flock to its temples and ghats -- or riverbank -- every year.
It is also politically significant. When Narendra Modi, then a state-level leader for the Hindu nationalist Bharatiya Janata Party (BJP), decided to seek national office in 2014, he chose the ancient city as his constituency.
"I feel Ma Ganga (Mother Ganges) has called me," Modi said in 2014. "I feel like a child who has returned to his mother's lap."
Varanasi was also the stage for the finale of India's elections -- the largest the world has ever seen -- as polling concluded there on Sunday, four days before results are announced.
In a speech on Tuesday, Modi reiterated his 2014 message to the people of Varanasi ahead of voting.
"It is often said that whosoever come to Kashi (the ancient name for Varanasi) even once, becomes part of the city. In the last five years, I have experienced this every passing moment. In molding me and giving a direction to my political and spiritual being, Kashi has a huge influence on me," he said, seeking re-election from the city.
With exit polls commissioned by private Indian media outlets suggesting Modi could be on course for a second term, CNN visits his constituency to examine how life has changed since he came to power -- and whether he was able to keep his previous election promises.
Cleaning up the world's fifth-most polluted river was never going to be easy. The river, which originates from a glacier in the Himalayas, is a lifeline for 400 million people -- but its waters have become dangerously toxic in places with billions of liters of pollutants pumped into it every day.
Yet Modi made it a key promise to clean up the entire river by 2020 under his Clean Ganges program. He pledged 200 billion rupees ($2.8 billion) starting from April 2015 to get it done.
In many ways, Varanasi is ground zero for that project.
Om Prakash, 43, has been rowing boats for tourists along the river for more than 10 years. When he first started, his family would drink, cook and bathe in it. "But today, the water is not even worthy of touching," he said.
Many Hindus believe that bathing in the Ganga's waters will absolve them of sins and achieve "moksha," or salvation, from the cycle of life and death.
But chemical waste from industrial factories, run-off from oil refineries, dye from tanneries and human waste is poured into the river, mere meters from where people bathe or even drink.
Prakash says he doesn't know what the money Modi pledged is being spent on as the river is still dirty.