With Nitish Kumar's JD(U) and Lalu Prasad's RJD burying their differences and finally launching the Janata Parivar, the BJP has a tough job ahead in seeking to win the Bihar electorate.

After days of speculation on whether the Janata Parivar will survive, its leader Samajwadi Party chief Mulayam Singh Yadav on Monday announced that Bihar Chief Minister Nitish Kumar will be the consensus chief ministerial candidate of the political front.

However, in what could well be a sign of an end to the political animosity in Bihar, it was Lalu Prasad Yadav who proposed Nitish's name to lead the front in the September-October elections.

Nitish and Lalu let go of their political rivalry to take on the BJP in July 2014, ahead of the by-elections to 10 seats, of which they together won six. The BJP, which held six of these 10 seats, won just four. Since then, sensing that their merger could well bring an end to the 'Modi wave', the regional factions, including JD-S and Samajwadi Party, have decided to get together and reclaim the nearly lost Bihar mandate.

This is a critical election, we cannot afford to lose it. But the united opposition will make it tougher for us,” a senior BJP leader told Indian Express.

There is immense pressure on the ruling party ever since its humiliating defeat in the Delhi elections. A win in Bihar, with a majority at that, is a must for the BJP if it has to prove that the Modi government at the Centre continues to enjoy the trust of the people and that it has been delivering on its achche din promise.

Here then are the key factors that will determine whether the BJP sinks or swims in Bihar.

Winning back the Dalit vote

The BJP will be hoping to win back all the assembly seats in the 31 Lok Sabha constituencies that it won in 2014. That would translate into well over 70 percent seats of the total 243. But, for the party to retain its constituencies, it will have to retain its Dalit and backward classes vote bank, both of which appear to be drifting away from the BJP.

In April, BJP president Amit Shah's held a maha rally, commemorating Ambedkar's 124th birth anniversary, where he claimed that it was only the BJP that could work for the welfare of the weaker sections.

"I want to tell Lalu that your alliance with JD(U) will yield zero results. Zero plus zero would be zero, no matter how hard you try," Shah said, in a way launching the BJP's political campaign in the state.

But wooing the Dalit vote will require negotiating the tricky decision as to whether the party should name a CM candidate, or not. The RSS, in a meeting in March this year, warned the BJP not to declare a CM candidate keeping in mind caste equations in the state, which are quite different from Maharashtra or Haryana, where the party swept to power, The Economic Times reported.

The powerful Sushil Modi, or SuMo as he is known, is the obvious CM choice, but naming him comes with a big downside.

As one BJP leader told Hindustan Times, “It becomes easier to select a person if you have the numbers. We did not find it difficult in Haryana, Maharashtra and Jharkhand where the party did not project a face but appointed a CM who did not belong to the dominant caste of that state."

The Nitish Kumar factor

With Lalu Prasad out of the game following his conviction in the fodder scam, the BJP is likely to train their guns at former ally Nitish Kumar - arguably Bihar's most popular CM in recent times, who in 2005 put an end to the 'jungle raj' of Lalu Prasad's RJD.

With Kumar ending the JD(U)-BJP ruling alliance in June 2013, the party now has fodder to attack Kumar on the same issues, threatening to 'expose' corruption and law & order issues that they claim have risen in the state.

However, Nitish Kumar has help, and from the most unlikely source: One of Modi's significant campaign advisors, Prashant Kishor.

Kishor, an integral part of Citizens for Accountable Governance, had been involved in Modi's public campaigning since 2011. In run-up to the 2014 elections, Kishor was reportedly the key architect of the 'Chai Pe Charcha' and 3D hologram campaigns, besides helping build Modi's image on social media.

"We have approached him and talks are on. We are confident he will join us. Prashant Kishor has a proven track record in professional election campaigning by connecting cadre to voters, and he will be an asset for us," Pavan Varma, a key-aide of Nitish Kumar, told The Economic Times in May this year.

Manjhi ki nao kabhi nahin dubti hain

Expelled from the JD(U) for refusing to vacate the chief minister's post, former Bihar chief minister Jitan Ram Manjhi could play a key role in BJP's Bihar campaign, especially in terms of winning back the dalit vote.

While it is very unlikely that the BJP will project Manjhi as anything more than one of the campaign leaders, it will definitely use the Mahadalit leader to retain that critical vote share, as well as win back the Extremely Backward Caste votes - who constitute about 24 percent of Bihar's electorate.

Manjhi, who claimed that Nitish Kumar sacked him because he thought a Dalit would just be a rubber-stamp CM, dramatically said, "Manjhi ki nao kabhi nahin dubti hain (Manjhi’s boat never sinks)," days before he was removed as CM. His recent meeting with the PM in Delhi have fueled speculation that his boat may soon be firmly tethered to the BJP in Bihar.

"Manjhi has been acting as 'Mukhauta' (mask) of BJP from the beginning of his tenure as CM. His meeting with the PM has exposed the BJP's game plan of creating rift in the JD(U) through him," Bihar Congress president Ashok Choudhary told PTI. The JD(U), too, hit out at its former leader, with its spokesperson saying: "This indicates that an unethical alliance between Manjhi and the BJP is being formalised."

When asked if his party was open to an alliance with Manjhi or expelled RJD leader Pappu Yadav, BJP chief Amit Shah simply said, "Presently, talks are on. Our doors are open."

Congress backing off?

The Congress party is likely to take a back seat in these elections after its disastrous performance in the Lok Sabha elections, where it won just two of the 40 seats it contested. It was the same result in the 2010 Assembly elections, where the party managed just four of the 243 seats that it contested.

Congress vice president Rahul Gandhi, according to the Times of India, has been credited with 'nudging' Lalu to accept Nitish Kumar as the CM candidate. Asked about his meeting with Gandhi, Nitish said: "I had a scheduled meeting with Rahul Gandhi on Sunday in the backdrop that the Congress is very much part of the plan to firm up a broad alliance comprising the JD(U) and RJD among others for the assembly polls in Bihar."

With Congress content to play matchmaker and marriage counselor, the fight for power is likely to be a little less fractious for the Janata Parivar. While the alliance is yet to declare its seat-sharing formula, among the options being discussed is one wherein both RJD and JD(U) could contest 100 seats each while 43 could be left for Congress, CPI-M, CPI and the NCP.

In contrast, there is already speculation that a united opposition may increase BJP's alliance woes, as partners become more demanding. According to the Express, "While RLSP has demanded 40-50 seats, Paswan’s party is keen to contest at least 80 seats. The BJP, which has set a mission of 182 seats, wants to contest nearly 200 seats." And that doesn't include the demands of Manjhi's Hindustani Awam Morcha (HAM) if he is brought in to fight for the Dalit vote.

Just a few months ago, as the state government was torn apart by the nasty Manjhi-Nitish wars, Bihar seemed like a sure win for the BJP. Now, the road to victory looks longer and far more hazardous, and the price of defeat all the more steeper.