On the 76th day of his long march north through the entire length of India, Rahul Gandhi, scion of a once-mighty political dynasty, walked into a textile-making town in the middle of this vast country, his face and hair covered in dust.
Gone were the luxury trappings that his adversaries in India’s Hindu nationalist governing party had used to caricature him as entitled and aloof. Now, Mr. Gandhi was speaking of blistered feet and the struggle of the common man. He was shaking hands with children, hugging older men and women who caressed his hair and kissed his forehead, on what he hoped was a 2,000-mile journey out of the political wilderness for his once-dominant Congress party.
“Every democratic institution was shut for us by the government: Parliament, media, elections,” Mr. Gandhi, 52, told supporters late last month in Burhanpur, in the state of Madhya Pradesh. “There was no other way but to hit the streets to listen and connect with people.”
With a national election less than 16 months away, Mr. Gandhi’s march could determine whether India’s fractured political opposition can do anything to halt the era-defining ambitions of the governing Bharatiya Janata Party, led by Prime Minister Narendra Modi.
The future of India as a multiparty democracy hangs in the balance. Mr. Modi, one of the most powerful leaders in India’s history, has remade its secular political foundation to privilege the Hindu majority and sideline Muslims and other minorities.
His imprint is so deep, and his successes so complete, that his lieutenants say the B.J.P. will remain in control of the country for decades to come.
As the party has tightened its grip across the country and its institutions, opposition politicians complain that they have been pushed out of platforms where they can reach the masses in the cycle of democratic politics.
Parliament, once a thriving debate chamber, is now largely confined to ministerial speeches, with the governing party avoiding debates on key policy issues. The B.J.P., through a mix of pressure and the threat of withholding government advertising money, has largely cowed the traditional media.
After Mr. Gandhi reached Burhanpur, where a large crowd greeted him, with some watching from rooftops and others from the lean branches of trees, there was barely a mention of it on nightly television programs.
That Mr. Gandhi has found it necessary to walk the whole of India, fighting to steal a ray of the spotlight and project a new profile, is the culmination of a once-unimaginable reversal of fortune for his family and party.
The Indian National Congress party has led the country for two-thirds of its 75 years of independence, and the Gandhi-Nehru family has produced three prime ministers who governed for a total of nearly four decades.
But in Mr. Gandhi’s decade as the party’s official president or de facto leader, it has faced repeated defeats in national and state elections, and currently has just 53 of the 543 seats in Parliament. The B.J.P. has 303 seats.
With the party increasingly defined not by ideas but by loyalty to the family that has been central to its history, the dilemma around its decline is often simplified as: can’t do with or without the Gandhis.
As the Congress party has withered, its messy scandals and infighting have increasingly played out in public. The muddle created by the family’s inability to reconcile warring factions has resulted in stagnation at the local level, party officials say, and high-ranking defections.
“This march, of course, is a last-ditch attempt on his part to revive the fortunes of his party and to bolster his national image,” said Sumit Ganguly, a professor of political science at Indiana University. “But beyond the fanfare, he has failed to spell out a clear, alternative vision for the country.”
Mr. Gandhi said he started his journey — which will take roughly 150 days as he and his entourage of 120 cover about 13 miles a day, sleeping in containers hauled on heavy trucks — to help unite a country he says is deeply polarized by Mr. Modi’s Hindu majoritarian politics.
Since September, as he has passed through villages and small towns across seven states, his march has attracted a wide range of followers: farmers facing an inescapable cycle of debt; Indigenous people struggling to protect rainforests from powerful developers; students anxious about upward mobility in an economy failing to provide enough jobs.
In attacking the governing party, Mr. Gandhi has voiced the worries of a vast section of the population suffering from the deeply unequal reality of an economy hindered by high levels of youth unemployment and rising inflation.
“When he listened patiently to us and spoke of the pain of the common man, my opinion about him changed,” said Amar Thakur, who supported the B.J.P. in the last elections and met Mr. Gandhi during a meeting in Burhanpur to hear local grievances. “Enough of hate now, I will vote for his party.”
Mr. Gandhi’s simple message of unity, Congress leaders said, amounts to the party’s first major ideological assault against the Hindu-first idea of India being cemented by the B.J.P.
“It is our last roll of the dice,” said Jairam Ramesh, a former federal minister who has been walking with Mr. Gandhi. “We are putting everything we have in it. If we don’t make a difference through it, then there is a problem for us both as a party and as an ideology.”
Mr. Modi’s mark on Indian politics is so indelible that Mr. Gandhi, who declined to be interviewed for this article, has appeared to emulate him during his countrywide journey even as he has presented himself as an alternative.
Mr. Gandhi’s forehead has often been adorned with a red dot, or tilak, a mark of Hindu piety. He has shed his formerly clean-shaven look for a beard that is growing by the day. He often participates in temple visits and religious ceremonies as he stops in villages and towns.
Such long marches are part of a well-established political tradition in India dating back to the country’s independence struggle. In the 1990s, when the roles were reversed, the B.J.P. undertook a similar march, rallying around the construction of a Hindu temple where a Mughal-era mosque had stood. That march helped fire up the B.J.P.’s ideological base and set the stage for its subsequent rise.
It is far from clear whether Mr. Gandhi can bring his party back from a path to irrelevance in national politics. But he seems to be banking on a two-pronged strategy — at once putting himself at the center of the effort to build a narrative and direction while creating some distance by turning over the party presidency to someone outside the family.
After long periods of resentment within the Congress ranks about the Gandhi family’s refusal to share the leadership, the party in October elected an 80-year-old loyalist as its first non-Gandhi president in 24 years.
To some critics, the choice of the new leader, as well as the march’s singular focus on Mr. Gandhi, made clear that the family was not letting go in meaningful ways that could fix the party’s dysfunction and erosion of support.
Whether the Congress party’s fortunes change or not, it is clear that Mr. Gandhi’s message has resonated with many who view India’s direction under Mr. Modi with dismay.
On a recent morning at the border between the states of Maharashtra and Madhya Pradesh, hundreds of young men started chasing Mr. Gandhi, who walked inside a rope held by dozens of police officers in a square shape.
Syed Sharaft Ali, a Muslim day laborer, said he had left his home early in the morning and walked for three hours to express his support for Mr. Gandhi’s march and tell him how religious polarization was dividing friends and destroying families.
As Mr. Gandhi closed in, the crowd pushed Mr. Ali, his body rolling between officers as they tried to corral the well-wishers.
Mr. Gandhi gestured toward Mr. Ali to come inside the ring. They spoke for a minute.
“At least he hugged me,” Mr. Ali said. “Other leaders don’t even want to look at us.”
Mr. Ali then walked back toward his village with moist eyes; Mr. Gandhi continued on through the dust.
Mujib Mashal contributed reporting from New Delhi.
