Several BJP allies have left the NDA in the last four years. Others are bargaining hard for a better deal as talks over seat distribution gain momentum ahead of the 2019 general election.

In the current scenario, a situation of a trilateral contest on the ground between the BJP, Shiv Sena and Congress-NCP alliance in Maharashtra could prove more detrimental for Shiv Sena than for the BJP.

The discord in Maharashtra appears most visible where the Shiv Sena has had a running feud with the BJP - both at the centre and the state.

BJP national president Amit Shah, in a meeting with party cadre, dropped hints of going solo in Maharashtra after Shiv Sena chief Uddhav Thackeray had slammed the BJP over issues such as Ram temple in Ayodhya and even raked up the Rafale controversy.

In the opposition camp, NCP president Sharad Pawar said that a deal with Congress has been finalised on at least 45 of the total 48 seats in the state and a formal announcement can be expected soon once a settlement is arrived at on the remaining seats.

An analysis of the vote share of the four political parties in the 2014 Maharashtra state assembly elections and correlated those aggregates with parliamentary constituencies of the state to calculate how the parties would fare in terms of seats if the electorate voted the same way as it did in the state elections.

The vote share arithmetic shows that if Shiv Sena contests the coming elections on its own, it could lose out on at least 16 of its 18 seats to the Congress-NCP combine. The alliance would go from six seats to 23 seats in Parliament. On the other hand, the BJP would comfortably hold its fort, securing 23 seats that it had won in 2014.

Apart from securing the six seats (Baramati, Hingoli, Kolhapur, Madha, Nanded and Satara) that the Congress and NCP had won in 2014, they could together dethrone the BJP and Shiv Sena in Aurangabad, Buldhana, Dhule, Dindori, Hatkangle, Jalna, Latur, Mumbai South Central, Nandurbar, Osmanabad, Palghar, Parbhani, Raigad, Sangli, Shirdi, Shirur and Yavatmal-Washim in terms of Assembly elections 2014 vote share. The BJP makes up for its losses on other seats held by Shiv Sena.

However, if Shiv Sena and BJP come together again, they retain their 41 seats.

In 2014, BJP and Shiv Sena had contested the general elections together against Congress and NCP. The BJP-Shiv Sena combine accounted for 48.4 per cent of the vote share bagging 41 seats while Congress-NCP was reduced to 6 seats with 34.4 per cent of the votes polled.

However, the four parties fought separately in the state assembly elections held later that year. The vote share was 28.1 per cent, 19.5 per cent, 18.1 per cent and 17.4 per cent for the BJP, Shiv Sena, Congress and NCP, respectively.

But politics is much more than the arithmetic. While this arithmetic — on the basis of previous vote share - favours Congress-NCP in case of a triangular contest, the number of seats remain unchanged if Shiv Sena and BJP join hands one more time.

It is worth noting that the analysis is based on vote shares of these parties in late 2014, roughly 6 months after the general elections.

Four years later, BJP and Shiv Sena are the incumbents and Congress and NCP are in the opposition.

This comes at a time when the Congress and the Nationalist Congress Party have almost firmed up their alliance for the upcoming Lok Sabha elections and the uncertainty over the future of the BJP-Sena alliance remains.

Yet, the saffron party has decided to keep its doors open for an alliance with its bickering ally. Earlier, the chief spokesperson of Maharashtra BJP, Madhav Bhandari said, "We have fought the past Lok Sabha elections together. The situation hasn't changed."