• Congress president Sonia Gandhi cast her vote in the party's polls to elect her successor.
• Congress general secretary Priyanka Gandhi Vadra also accompanied her mother Sonia Gandhi and cast her vote
• It is a historic occasion, Cong only political party that has elections for post of president: Jairam Ramesh after casting his vote
• Congress presidential polls are free, fair and transparent: Jairam Ramesh

Voting began on Monday in the Congress presidential polls as senior leaders Mallikarjun Kharge and Shashi Tharoor face-off for the post of AICC chief.

Over 9,000 Pradesh Congress Committee (PCC) delegates form the electoral college to pick the party chief in a secret ballot.

Voting began at 10 am at the AICC headquarters here and at party's polling booths in state offices across the country.

Veteran Congress leader P Chidambaram was the first to cast his vote at the AICC headquarters here, sources said.

Kharge is considered the favourite for his perceived proximity to the Gandhis and backing by senior leaders, even as Tharoor has pitched himself as the candidate of change.

During the campaign, even though Tharoor raised issues of uneven playing field, both candidates and the party have maintained that the Gandhis are neutral and that there is no "official candidate".

While party chief Sonia Gandhi and Congress general secretary Priyanka Gandhi Vadra voted at the AICC headquarters here, Rahul Gandhi will be voting at the 'Bharat Jodo Yatra' campsite in Karnataka's Sanganakallu in Ballari along with around 40 other 'Bharat Yatris' who are PCC delegates.

Tharoor will cast his vote at the Kerala Congress headquarters at Thiruvananthapuram, while Kharge will do so at the Karnataka Congress office in Bengaluru.

Ahead of the polling, Kharge had said he would have no shame in taking the advice and support of the Gandhi family in running the party affairs, in case he becomes its president, as they have struggled and put their strength for its growth.

The veteran leader had said he is the "delegates' candidate" in these polls.

Tharoor on his part had taken a veiled dig at some senior leaders supporting Kharge, saying some colleagues were "indulging in 'netagiri' and telling party workers" that they know whom Sonia Gandhi wants elected.

If anyone has "fear or doubt" in their mind, the party has made it clear that it will be a secret ballot, he had said in Lucknow on Sunday and urged the Congress delegates to listen to their hearts while voting to elect the new party president.

While the Kharge camp had shared a campaign video seeking votes for him which included visuals of him walking with Rahul Gandhi in the Bharat Jodo Yatra with the song 'Kandhon se milte hain kandhe' from the movie Lakshya playing in the background, Tharoor had issued a fervent video appeal on Twitter calling on electors to show courage to "embrace change".

Tharoor had asserted that in the change he envisions, the party's "values and loyalties" will remain the same with only the ways of achieving the goals undergoing a transformation.

Electors in the Congress presidential polls have been asked to put a tick mark against the name of their choice on the ballot paper after AICC president candidate Tharoor's team took up with the party's top poll body the issue of its earlier directive that voters write "1" to reflect their preference, citing that it may lead to confusion.

"The voters are instructed to put a tick mark in the box in front of the candidate whom they wish to vote for. Putting any other symbol or writing a number would make the vote invalid," the directive from Mistry's office had said.

Asked about the significance of the polls, Congress general secretary in-charge communications Jairam Ramesh had told PTI that he has always believed in the Congress model of evolving a consensus for such positions.