The BJP's surprise decision to back Shiv Sena rebel Eknath Shinde as Maharashtra's next chief minister underlines its aim to bring aboard its Hindutva bandwagon the regional sentiments plank traditionally identified with its former ally, with the party's eyes firmly set on the bigger battles of the 2024 Lok Sabha polls and the state elections the same year.

Once a junior ally of Shiv Sena which advocated a more unabashed form of Hindutva, the BJP now virtually owns it, and hopes Shinde will help the BJP, in its elevated position, to identify with the regional sentiments, which the Sena always championed.

The strategic move will also bolster the BJP's push to decimate Uddhav Thackeray-led party by depriving it of its pet Hindutva and ethnic sub-nationalism plank.

The pull of rank and file Shiv Sainiks towards the Shinde faction may also gain strength with one of them at the top post, BJP insiders said.

With Marathas, the state's most dominant caste, considered more sympathetic to the parties like the Nationalist Congress Party and the Shiv Sena, Shinde will also help the BJP in wooing the community that he comes from.

As the fight between two Sena factions intensify in the coming weeks and months, including before the Election Commission, the rise of Shinde, a grassroots Maratha politician always identified with his party's planks of Hindutva and ethnic sub-nationalism, may hurt the prospects of Uddhav Thackeray.

"It is a very strategic move. It appears to be a plan of a much larger strategy where the aim is to weaken the Shiv Sena and take it out of the hands of Thackerays," said Maharashtra-based political scientist Sanjay Patil, who has studied the party for his Ph.D.

"Using Shiv Sena slogans, its people and by appointing a Maratha CM, the BJP is posing the toughest challenge to the Thackeray brand in the history of Maharashtra. There is an attempt to separate Thackerays from Shiv Sena, but it wouldn't be easy as Sena and Thackeray were always the same in the imagination of Marathi people," he said.

"As Sena's ideology was broadly based on two planks: religion (Hindutva) and region (Marathi Manoos), now the attempt is that everything gets submerged into the larger plank of Hindutva and should be bigger than nativism," he added.

There is also a view that the BJP may have tried to hedge its bets as the matter is still technically in court, and it remains an open guess how the battle between the two Sena factions will play out politically as the brand Thackeray can't be written off.

The BJP's move, however, has also come with its own share of headache.

Former Maharashtra chief minister Devendra Fadnavis, who is seen as the party's face in the state and a key leader behind the rebellion in Shiv Sena, was apparently left unhappy with the leadership's choice of Shinde.

He announced that he will not be part of the new Cabinet but was prevailed up on by the top brass to join it.

Political observers also pointed out that Shinde, whose faction has around 50 MLAs (including independents) to the BJP's 106, leading the government may have its own pitfalls.

Political benefits of the leaders of rebel factions or the smaller party running the government with the support of a big party have been mixed.

S Gurumurthy, an RSS sympathiser and editor of Tamil political weekly Thuglak and, lauded the BJP's move to pick Shinde as chief minister as "strategically brilliant and politically large-hearted".

It has shocked political pundits seeing a BJP conspiracy behind the revolt in Shiv Sena, he said.

Political observers said Shinde as chief minister will also be a part of the BJP's plan to further consolidate its position in its stronghold in the northwest region of the country after it had suffered some reverses in the last round of assembly polls in states like Gujarat, Rajasthan, Madhya Pradesh and Maharashtra.

It had come to power in Gujarat in 2017 with a reduced mandate against a spirited fight from the Congress and had lost power to the opposition party in Rajasthan and Madhya Pradesh in 2018.

The Sena's decision to snap ties with the BJP cost the party a chance to retain power in Maharashtra after the 2019 assembly polls despite emerging as the largest party.

Since those polls, the BJP has come to power in Madhya Pradesh following a rebellion in the Congress by MLAs led by Jyotiraditya Scindia, now a Union minister after joining saffron party along with his followers.

It is also seen to have strengthened its position in Gujarat with the Congress suffering defections and losses in bypolls and local polls. Its return to power in Maharashtra further boosts its footprints in the entire north-west region, which it had swept in the last two Lok Sabha polls.