However, the role of Rahul Gandhi in the 2014 polls will be decided later, said general secretary Janardan Dwivedi.
This sets the ground for his not only taking major election decisions, but as a possible prime ministerial candidate.
Rahul Gandhi heads the party's coordination panel for the 2014 polls.
A new post was re-created especially for Rahul Gandhi. The last vice president was Arjun Singh when Rajiv Gandhi was prime minister and party chief.
After he was elected the new vice president, Rahul Gandhi thanked the leaders and said he is "confident" that they could "transform the party."
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While Highways Minister CP Joshi hailed the move as representing "new leadership for the new India" Youth Congress chief Rajeev Satav said it was a historic day and would bring joy to the young friends of the party.
"He has travelled across the country in the past eight years and understands it," said Joshi.
This would be remembered as the real Jaipur Declaration much over the formal document to be adopted by the All India Congress Committee Jan 20, quipped another minister.
Much before the Dwivedi announced the CWC decision, hundreds of elated Youth Congress members started celebrations outside the Birla auditorium, venue of the "Chintan Shivir" and also outside 10 Janpath, the residence of party chief Sonia Gandhi in Delhi.
Party insiders said Rahul became the youngest vice president after Jitendra Prasada, who got the position at 50 plus age.
Prasada's son Jitin is Minister of State for Human Resource Development and a member of Rahul's team.
"He will try and live up to the expectations of a new India," said Jitin Prasada.
Joshi said Rahul has already democratised the party' youth wings ending a culture of patronage and his ideas will help the party regain strength across the country.
The new leader will make his own team now, said Joshi.
Party insiders said this would mean more younger leaders will get important roles in the organizational reshuffle, which is likely to follow soon marking the generational shift.
In the last cabinet reshuffle Oct 28, 2012, Rahul's influence was clear when he suggested for promotion many younger leaders, including Prasada, Corporate Affairs Minister Sachin Pilot and Information and Broadcasting Minister Manish Tewari.
A pointer to Rahul's elevation as official number two came when party leaders and ministers competed with each other in demanding a bigger role for him at the introspection meet.
The largest ever presence of over 130 Youth Congress and NSUI members out of the 350 delegates at the strategy session was also at his behest.
The decision approved by the Congress Working Committee, the party's highest decision making body, makes him officially the number two in the party after his mother and Congress chief Sonia Gandhi.
"With his appointment as vice president of the Congress party today, Rahul Gandhi has been elevated to number two position in the party," Dwivedi told reporters, amid scenes of wild jubilation by Congress workers and supporters.
The supporters also demanded that Rahul Gandhi be named the Congress' prime ministerial candidate for the 2014 Lok Sabha elections.
"This decision will greatly strengthen the party and the hands of the Congress president," Dwivedi said.
Prime Minister Manmohan Singh was the first to offer Rahul Gandhi a bouquet. Thereafter, a host of leaders lined up to offer him boquets and garland him.
As soon as the announcement was made, supporters cheered and danced to drum beats, waving posters of Rahul Gandhi. The city sky scape was lit up with sparkling pyrotechnic fireworks.
Asked whether Rahul Gandhi would be pitted against Gujarat Chief Minister Narendra Modi in 2014, Minister of state for Home R.P.N. Singh said the Bharatiya Janata Party (BJP) had not as yet decided on its prime ministerial candidate. Modi is being touted as the BJP's frontrunner for the top post.
"When he is the face of the Congress party, when we come back to power in UPA-III we will support him (as PM)."
Party spokesperson Sandeep Dikshit said Rahul Gandhi will be the "chief campaigner" for the elections, but the "high command" will take a final decision on his prime ministerial candidature.
The BJP termed the decision was a "mere eyewash".
BJP spokesperson Rajiv Pratap Rudy said: "After hearing the announcement, I felt very amazed that a member of the same family is getting a post in the same party..It is something hilarious."
(Amit Agnihotri can be contacted at amit.a@ians.in)