Rahul Gandhi, scion of India's Nehru-Gandhi dynasty, addressed tens of thousands of supporters at a rally in New Delhi on Sunday, raising his profile before a possible bid to become prime minister.
Gandhi, 42, whose father, grandmother and great-grandfather all led India, vowed to fight to modernise the country through reforms that he said would help the poor and provide jobs for the rapidly growing population.
"We need economic reforms because only when businesses operate well will there be progress, and then we can run programmes to benefit the poor," he told the major Congress party gathering in the capital.
Gandhi vowed to help push through policy changes that will transform India's retail sector by allowing global supermarket chains such as Walmart and Tesco to open in India and tap into its burgeoning consumer market.
"The world is saying that India is standing up," he said. "The youth here will show not just India but also the whole world the way forward."
General elections are not due in India until 2014, but the Congress-led government has suffered a difficult few years in power and its leaders are eager to revive momentum in the long run-up to polls.
Manmohan Singh, the current prime minister, has been buffeted by falling economic growth, a parliamentary deadlock that has scuppered his legislative plans and a damaging series of corruption scandals.
Singh, 80, who also spoke at the event, is expected to step down before the election, with pressure on Gandhi to take a shot at the premiership in an effort to continue his family's long domination of Indian public life.
The dynasty is descended through Jawaharlal Nehru, India's first prime minister after independence in 1947, his daughter Indira Gandhi, who was twice premier, and Indira's son Rajiv.
But Rahul Gandhi's appetite for India's turbulent political scene has often be questioned by critics. He has declined to take on any ministerial responsibilities, concentrating instead on leading the Congress youth wing.
One foray he made into electoral politics earlier this year was a bruising experience, when he organised the Congress's campaign in the key state of Uttar Pradesh but failed to capture many of the seats that the party targeted.
Gandhi told the crowd in Delhi that, despite coming from within India's ruling elite, he was determined to break open the country's "closed political system".
"Young MPs tell me that you all want to change the system, and together we can," he told the rally. "The biggest problem is that our political system is shut for the common man."
Gandhi's mother Sonia, who is president of the Congress party, followed his speech with a spirited attack on the opposition Bharatiya Janata Party (BJP), which has launched repeated attacks on the government for alleged corruption.
Italian-born Gandhi, considered the most powerful politician in India, described corruption as "an illness, a cancer which kills the poor" and insisted that Congress was cracking down on all forms of graft.
"If anything is proven, there will be no saving the corrupt," she said, accusing the BJP of being "steeped in the mud of corruption".