Shimla, Oct 29 : After a month-long hectic political activity, the by-polls for the Mandi parliamentary constituency and three Assembly seats in BJP-ruled Himachal Pradesh will be held on Saturday. The counting of ballots will take place on November 2. The by-poll for Mandi was necessitated following the death of Bharatiya Janata Party MP Ram Swaroop Sharma. The three Assembly seats -- Jubbal Kotkhai (Shimla district), Fatehpur (Kangra district) and Arki (Solan district) -- had fallen vacant after the demise of Narinder Bragta of the BJP, Sujan Singh Pathania of the Congress and former six-time Chief Minister Virbhadra Singh of the Congress, respectively. Political experts say it is a battle between the past performance of Congress stalwart and six-time Chief Minister late Virbhadra Singh and his legacy and BJP's Chief Minister Jairam Thakur's credibility during the parliamentary by-poll in Mandi, one of the country's toughest and sprawling constituency. The saffron party has pitted Brigadier Khushal Thakur (retired), a decorated officer who played a crucial role in the 1999 Kargil war, against Congress' Pratibha Singh, a two-time MP from Mandi. The seat -- a prestigious one for Chief Minister Thakur as it falls in his home district -- fell vacant with the death of two-time BJP MP Sharma, who defeated Congress candidate Ashray Sharma, the grandson of former Telecommunications Minister Sukh Ram in his electoral debut, with a record margin. Eyeing sympathy votes, Pratibha Singh, who is banking largely on her first-time legislator son Vikramaditya Singh for campaigning, sought votes on development carried out by her husband during his three stints as an MP from Mandi and six terms as the Chief Minister. Pratibha Singh, who lost the Mandi seat in the 2014 Lok Sabha elections, missed no opportunity to remind the electorate that the victory in the Mandi by-election "will be a tribute to him (Virbhadra Singh)". The Chief Minister sought votes on the valour and integrity of the Kargil war hero. "Everybody knows about the valour of Brigadier Khushal Thakur. He fought the Kargil battle valiantly. It is saddening that Pratibha Singh described the battle with Pakistan a minor one," said the Chief Minister, who missed no opportunity to remind the voters that the credit for popularising Mandi as Chotti Kashi went to the late MP. Even the Prime Minister's speeches had a mention of Chotti Kashi. For the five-time legislator Thakur, development, welfare and no witch hunting have been the mantras of success. He says his government is working without any vendetta and vengeance towards political opponents. The main contest in Mandi is between the BJP and the Congress. The Mandi constituency, which includes Kullu, Mandi and some areas of Chamba and Shimla districts, besides the tribal-dominated Kinnaur and Lahaul and Spiti, is one of the biggest in the country. The Jubbal-Kotkhai Assembly by-poll is set for a keen triangular contest. The presence of BJP rebel Chetan Bragta, son of former Horticulture Minister Narinder Bragta, in the fray as an Independent candidate is bound to make a dent in the ruling party's vote bank. Two-time former BJP legislator Govind Ram Sharma is another disgruntled BJP leader, who has not campaigned for his party candidate Rattan Pal. The Fatehpur assembly is all set to witness a triangular fight between Congress candidate Bhawani Pathania, BJP nominee Baldev Thakur and Independent candidate Rajan Sushant. /IANS