Shiv Sena chief Bal Thackeray has sought to nip in the bud Bharatiya Janata Party leaders' efforts to project Narendra Modi [Images] as an election winner, causing unease in the already uneasy Sena-BJP alliance.

Thackeray's remarks that only the Sena pattern -- and not Modi -- will work in Maharashtra, is being viewed as a reminder to top state BJP leaders who want to replicate the 'Modi effect' in the state.

Sena is the senior partner in the over two-decade old saffron alliance, which has seen a lot of turbulence after the killing of Pramod Mahajan, the main architect of the alliance.

While Sena has 56 Members of Legislative Assembly in the 289-member state Assembly, BJP has 54. In the Legislative Council, Sena has nine members against 13 of the BJP.

After Modi's public rally in Mumbai on January 20, some BJP leaders were quoted as saying that the party would use the 'Modi pattern', which was so successful in Gujarat, in Maharashtra as well.

In fact, state BJP president Nitin Gadkari, while speaking at the rally, said Modi should help the party win the Maharashtra polls.

Three days after the Modi rally, Thackeray, who turned 82 on January 23, sought to put a stop to the BJP leaders' plans, saying 'only the Sena pattern will work in Maharashtra'.

Relations between the alliance partners have soured in the recent past. The alliance was on the verge of collapse after the two parties fought bitterly on who should contest the Chimur assembly bypoll two years ago.

Gadkari had made the seat, which fell in his Vidarbha region, a prestige issue. After a truce was reached, Sena agreed to let BJP contest the seat, but BJP lost the bypoll.

Senior BJP leaders had criticised the style of functioning of Thackeray's son, Sena's executive president Uddhav. "He doesn't even care to accept our phone calls," a top BJP leader had said.

The ties between the two parties were at their lowest ebb last year when the Sena angered the BJP by deciding to support the Congress-backed candidate in the Presidential poll,  contrary to BJP's expectation that it would back the National Democratic Alliance nominee.

The Sena harped on the Marathi asmita (pride) card to justify its support to Pratibha Patil [Images], saying she was the 'daughter of Maharashtra' and the opportunity to have the first Maharashtrian, that too a woman, in Rashtrapati Bhawan, should not be squandered.

This evoked sharp criticism from the BJP, with senior leader Gopinath Munde accusing the Sena of betraying the alliance dharma.

Following Uddhav Thackeray's meeting with L K Advani at the latter's Delhi residence, it was announced that the differences between the alliance partners had been sorted out.

Advani later visited the Thackeray residence in suburban Bandra and leaders of both the parties said the alliance would work with renewed vigour to wrest Maharashtra from the Congress-NCP alliance, now into its second term.

Now, when BJP has declared Advani as its Prime Ministerial candidate, the Sena, while backing Advani, has shown a soft corner for another leader, Nationalist Congress Party chief and Thackeray's old friend Sharad Pawar [Images].

"Pawar is a competent person for the post of Prime Minister," Thackeray said in a recent interview. In the same interview, Thackeray lauded Advani's qualities, saying he was made of a different mould.

"The Sena chief should make his stance clear -- does he back Advani for the PM's post or is he supporting Pawar," a senior state BJP leader said, not ruling out another confrontation between the alliance partners as was noticed during last year's Presidential poll.

The Sena's perceived closeness to NCP is also a cause of concern for Maharashtra BJP leaders. "We will not be surprised if Pawar and Thackeray decide to ditch their respective alliance partners and come together, if it would result in forming the next government in the state," a Congress leader said.