The alliance of the United Opposition that is beginning to take shape may be up for its first big test on the national level when the election of the Deputy Chairman of the Rajya Sabha. The post is currently held by PJ Kurien, Congress MP from Kerala who was denied another term to the Upper House by his party. It is highly likely that the Congress will be pushing for some other candidate of its choice for the post. While the elections for the chairman of the house, who also serves as the Vice-President of India, is a long process, the deputy chairman is elected through a simple voting by members of the Rajya Sabha alone. While the BJP serves as the single largest party with 69 seats, it is way behind the majority mark in the 245-member house. The Congress, on the hand, has 51 members and garnering support for its candidate is going to be a tough task for the Congress before 2019. It is perhaps with this in mind that senior Congress leader Ahmed Patel reportedly met TMC chief Mamata Banerjee on Sunday. The election will also signify the level of understanding that different parties in the united Opposition share. The meeting came in the backdrop of Bahujan Samaj Party's denial to support the grand old party in Madhya Pradesh elections. Also, there's a difference of opinion between the Congress and other opposition parties on supporting Delhi Chief Minister Arvind Kejriwal against the Centre and Delhi Lt Governor Anil Baijal. As per a report, TMC's leader Derek O'Brien has been tasked with fielding a non-Congress, but a Congress-backed candidate from the opposition. The names of TMC MP Sukhendu Sekhar Roy and BJD leader Prasanna Acharya are doing the rounds for the post. On the other hand, a combative Bharatiya Janata Party (BJP) is likely to have its own nominee for the Deputy Chairman\u2019s post and will also seek to negotiate from other party members. Three regional parties - BJD, TRS, and YSRCP - which hold the key to the election are being wooed by both the ruling NDA and the opposition parties. However, BJD with 9 members in the Upper House, has been maintaining equal distance from both the BJP and the Congress. Similarly, the other two parties - TRS with 6 members and the YSRCP with two members - are yet to open their cards but are unlikely to go with the saffron fold.