Congress party supporters celebrate outside the party headquarters after the appointment of Rahul Gandhi as vice president of the party in New Delhi, India on Jan. 19, 2013. (Altaf Qadri/AP)

The latest heir apparent to India’s oldest and most powerful political dynasty was elevated Saturday to the ruling Congress party’s second-highest post, a move that the party hopes will revive its fortunes ahead of national elections expected later this year.

Rahul Gandhi’s highly anticipated appointment as vice president, made at a Congress gathering in the northern city of Jaipur, marks a significant generational shift in the 127-year old party, which his mother, Sonia Gandhi, 66, heads as president. The move follows several years of hesi­ta­tion by the 42-year-old scion, a delay that had prompted the news magazine India Today to dub him “Reluctant Rahul” and “heir not apparent.”

Rahul Gandhi has been a member of Parliament since 2004, representing Amethi, a poor rural district in northern India long held by his family.

Party leaders hope that his elevation will lift Congress’s dwindling credibility at a time when its coalition government in New Delhi, headed by Prime Minister Manmohan Singh since 2004, has been the target of public anger over corruption scandals, rising prices and violence against women.

“This will bring new energy to the party and galvanize our cadres,” said a jubilant Sanjay Nirupam, a party spokesman. “He will attract the country’s youth, will bring fresh ideas and a new style of working.”

In this April 25, 2009 file photo, India's ruling Congress party leader Rahul Gandhi smiles as he addresses a press conference in Kolkata, India. (Sucheta Das/AP)

Another party leader, R.P.N. Singh, called the younger Gandhi’s appointment a “game-changer” in a country where two-thirds of Indians are younger than 35 but the average age of politicians is more than 60.

Party leader Janardhan Dwivedi told reporters that when Gandhi’s name was proposed for promotion, members at the meeting “welcomed it by thumping their desks.” Television images showed party colleagues garlanding him with white chrysanthemums.

Fireworks lit up the night sky in Jaipur after the announcement, and drummers and dancers bearing flowers, flags and images of Gandhi thronged the meeting site there and outside Congress party headquarters in New Delhi. One placard read, “Rahul Gandhi is the pulse of young India.”

Some critics note, however, that the shy, dimpled bachelor has largely remained silent on many of the issues that have consumed the nation in recent months.

Gandhi did not go out and meet with the young people protesting a woman’s gang rape and killing last month, meeting privately with a small handpicked group instead and later issuing a bland written statement voicing regret at the rape victim’s death. Many protesters held signs saying: “India’s youth is here. Where are you, Rahul Gandhi?”

In recent years, though, he has carefully constructed a public image through a series of photo opportunities designed to capture him in roles relevant to both the old and the new India — visiting homes of impoverished villagers and squatting on their dirt floors to eat with them, cheering at cricket games from box seats and visiting college campuses to urge students to join his party.

After leading her party to an impressive win in the 2004 national elections, Gandhi’s Italian-born mother opted to become a backroom powerhouse and appointed the 80-year old economist Manmohan Singh as prime minister. Many believed she intended Singh to keep the seat warm for her son until he was ready.

It is not immediately clear whether Gandhi will become the party’s prime ministerial candidate in the next elections, which are scheduled for 2014 but which many observers say may be held this year because of internal friction in the ruling coalition.

Until now, Rahul Gandhi has been one of the Congress party’s six general secretaries and heads the party’s election campaign committee. He has chosen not to be part of Singh’s cabinet, despite clamor for him to do so from both the party and the government.

“The Congress party’s best bet right now is to rely on the Gandhi family name, which still has a lot of resonance across India and appeals to different sections of caste and religious groups,” said Rasheed Kidwai, the author of two books on the Congress party. “After nine years of Singh’s bland rule, the party has been crying for the charisma of the family again.”

Still, he cautioned, “India has changed a lot in the last decade, and we will have to see how the family reinvents itself.”

Gandhi will address party workers on Sunday in Jaipur.