India's main opposition Congress party on Wednesday announced that 47-year-old Priyanka Gandhi will look after the party affairs in the eastern part of Uttar Pradesh, the nation's politically most important state.

Priyanka Gandhi hails from the Nehru-Gandhi dynasty and is the daughter of Rajiv Gandhi and Sonia Gandhi. The family has dominated politics in India since its independence from British rule in 1947. It has so far produced three prime ministers, with Priyanka's father, Rajiv Gandhi, grandmother, Indira Gandhi, and great-grandfather, Jawaharlal Nehru, all serving as Indian prime ministers.

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Priyanka previously helped her mother and brother, Congress party President Rahul Gandhi, during election campaigning in their constituencies, but had never held an official party post.

Speculation regarding her entry into politics has been around for a long time. Many Congress party leaders and supporters have long urged her to play an active role in politics.

Following the announcement of Priyanka Gandhi's party role, Congress supporters started celebrating, bursting firecrackers and distributing sweets. The party said it was now "all fired up and ready to go" for the general election. 

"I am very pleased personally that my sister who is very capable will work with me," Rahul Gandhi told reporters.

Priyanka Gandhi's husband Robert Vadra also congratulated her after the appointment. "Congratulations P... always by your side in every phase of your life. Give it your best," he wrote in a Facebook post.

A popular figure

India's main opposition Congress party has long been under the control of the Nehru-Gandhi family. The Gandhis and their charisma have always been hugely important to the party to win elections.

That's why many Congress supporters view Priyanka Gandhi's entry as a "game-changer" for the opposition party, as she is regarded as a good orator and crowd puller. Many in India consider Priyanka to be a more popular figure than her brother Rahul, who has had the image of being a reluctant leader.  

During her public appearances, Priyanka has seemed to draw large crowds wherever she goes and connect easily with people. The party hopes to use her popularity in the upcoming general elections where it will be challenging Prime Minister Narendra Modi's Bharatiya Janata Party (BJP).

Priyanka's striking resemblance of her grandmother and late Prime Minister Indira Gandhi is also a big draw for Congress party workers and voters.

After the announcement, Congress supporters were seen outside the party office in Lucknow holding placards saying, "Indira is back."

But Priyanka's appointment has given ammunition to the ruling BJP to criticize the Congress as a "family concern."

Senior BJP leaders targeted the opposition party following the announcement. 

"Priyanka Gandhi furthered the legacy of Gandhi Congress Pvt Limited and officially becomes the General Secretary of @INCIndia. It is also the first official declaration from congress that they don't have trust in Rahul Gandhi's leadership" (sic), tweeted senior BJP leader and India's Health Minister JP Nadda.

"Expected, to promote dynasty is what Congress is all about. They consider family as the party while BJP considers party as the family. Congress has accepted that Rahul Gandhi Ji has failed," another BJP leader Sambit Patra was quoted by news agency ANI as saying.

Tough job

Priyanka Gandhi will take up the party position in Uttar Pradesh in the first week of February and this will be her first official party activity. 

Uttar Pradesh is a vast state in northern India with a population of over 200 million, making it the country's most populous state by far.

The state sends the highest number of lawmakers, 80, to the lower house of India's parliament, the 545-member Lok Sabha. It's therefore crucial for government formation at the national level.

The Congress party is expected to face a tough election battle in the state. But Congress supporters hope Priyanka Gandhi's entry into active politics will improve the party's electoral prospects.