(Bloomberg) -- The era of India’s coalition politics is back.

With Prime Minister Narendra Modi’s 2014 wave of popularity receding, polls show the ruling Bharatiya Janata Party may fall short of a full majority in next year’s federal election, prompting the country’s opposition parties to put aside their ideological differences and unite.

A key test of this new alliance will come today when Modi’s government faces its first no-confidence vote in the parliament. While the ruling coalition is expected to defeat the motion with its majority in the lower house, the outcome will reveal which group has been more successful in pulling smaller and non-aligned parties into its fold. It’s the first no-confidence vote to come before the parliament in 15 years.

“What is important is to see how many votes each side gets and which side has more cracks -- the opposition or ruling coalition,” said Arati Jerath, a New Delhi-based author and political analyst.

The federal election will determine whether Modi continues the economic and social reforms he put in place after winning the largest majority in three decades. He introduced a nationwide goods and services tax and banned on 86 percent of the country’s currency in a bid to stamp out unaccounted wealth. But the GST’s chaotic implementation, along with a banking credit crisis and growing discontent in rural areas are adding to voter concerns.

The Congress Party, led by Rahul Gandhi, has already reached an understanding with other opposition parties for India-wide cooperation, and it’s now working with small regional parties to build state-specific coalitions, said Congress leaders familiar with the development who asked not to be identified as they are not authorized to speak to the media. The party is negotiating with regional leaders in up to a dozen states to improve its lowest ever performance at the 2014 election and block BJP from retaining power, they said.

“Coalition politics is the reality and it is there,” P.L. Punia, a senior member of the Congress party said, without giving details. “It’s not a straight-jacket formula. Our policy on coalition is a state-wise assessment and a state-wise decision.”

Countering Modi

It was the reversal of the BJP’s fortunes in the southern state of Karnataka -- where it emerged as the single largest party but was ousted by a last-minute coalition cobbled together by the Congress party and the regional Janata Dal (Secular) party -- that marked the turning point for the country’s divided opposition.

Looking to 2019, it may be difficult for BJP to repeat its last performance in states of Uttar Pradesh, Gujarat, Madhya Pradesh, Rajasthan and Chhattisgarh, where it nearly swept all the seats in 2014, said Harish Ramaswamy, political analyst and professor of political science at Karnatak University. Modi’s electoral standing has reduced because of discontent by farmers and Dalits within the ruling party, Ramaswamy said by phone.

The BJP is likely to lose around 50 seats from these five states, reducing its overall strength from 282 to less than 200 throughout the country, which falls short of a majority in 543-member lower house of parliament, he said.

“As no grouping is getting close to a majority, pre-poll alliances are becoming more inevitable,” said Ramaswamy. “The strategy of opposition parties is not to concentrate on their votes, their seats; but to destroy votes of BJP."

BJP had forged an alliance with as many as 28 parties in the last election, even though the support of regional parties was redundant when the BJP alone got enough seats for a majority. Congress party, which had tied up with about 10 parties in 2014, this time seeks to increase its number of allies.

Congress party is working to forge alliance in states that include Madhya Pradesh, Chhattisgarh, Jharkhand, Uttar Pradesh, Bihar, Karnataka, Tamil Nadu, Maharashtra, Odisha and Jammu & Kashmir, the party leaders said. It is in talks with Maywati, leader of the Bahujan Samaj Party, for alliance separately for Uttar Pradesh, Madhya Pradesh and Chhattisgarh, they said.

Mayawati is talking to Congress on alliance matters and she will take the final decision, said Satish Chandra Misra, a senior BSP leader.

Even as BJP has extended its footprints across 19 of India’s 29 states, maintaining allies has proven difficult. Since March, two key partners -- the Telugu Desam Party in Andhra Pradesh and the People’s Democratic Party in Kashmir, quit the coalition called National Democratic Alliance or NDA. Another ally, Shiv Sena, is showing restiveness. These three parties make up 35 seats.

Still, BJP leaders are hopeful that the no-confidence motion will provide an opportunity to expose the opposition’s continued weakness. “We are hopeful that we will get support from parties outside NDA as well,” Ananth Kumar, parliamentary affairs minister, told reporters on Wednesday.

Ahead of the vote today, parties like the All India Anna Dravida Munnetra Kazhagam Party, Biju Janata Dal and Telangana Rashtra Samithi, are keeping their cards close to the chest. These parties account for 68 seats in the lower house.

"The more regional parties you have, the wider will be your net,” Jerath said.

To contact the reporters on this story: Bibhudatta Pradhan in New Delhi at bpradhan@bloomberg.net;Abhijit Roy Chowdhury in New Delhi at achowdhury11@bloomberg.net

To contact the editors responsible for this story: Ruth Pollard at rpollard2@bloomberg.net, Unni Krishnan

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