As the Manmohan Singh [Images] government braces for its first trust vote, the numbers game will be a dicey affair with fence sitters expected to have a field day.

The Nuclear deal explained

Be it Ajit Singh's Rashtriya Lok Dal or Janata Dal-Secular of former prime minister H D Deve Gowda or other smaller parties and Independents, all have the potential to upset the applecart of the Congress-led United Progressive Alliance coalition.

As one Congress leader put it, 'this is the first confidence vote where the tenth schedule (anti-defection law) would be of no use' as the Lok Sabha elections are round the corner.

Analysis: Options before the UPA

But, the suspense over the trust vote has deepened more as main opposition BJP appears reluctant to make much noise, which could create unnecessary problems for Left parties, whose withdrawal of support has led to the trust vote.

As there are nearly a dozen fence sitters in the Lok Sabha, both the government and the opposition are pinning high hopes on them and expecting their support.

Little to fault in IAEA agreement

In the Lok Sabha having an effective strength of 543, the ruling side has to cross the halfway mark of 272 to prove a simple majority and minus the support of these undecided parliamentarians.

The ruling UPA has an assured support of 221 lawmakers belonging to alliance partners, which includes the Congress' 153, Rashtriya Janata Dal's 24, Dravida Munnetra Kazhagam's 16 and Nationalist Congress Party's 11. However, the five-MP Jharkhand Mukti Morcha, although an ally of the UPA, has not yet revealed its cards.

Why PM and Karat should read this

Even if all JMM MPs support the government along with 37 MPs of Samajwadi Party and around half-a-dozen others, the treasury side will still be falling short by four votes.

In such a scenario, small parties like RLD with three MPs and JD(S) and National Conference, having two members each, will have a major say.

The delimitation of constituencies has added another dimension to the trial of strength as several members will be losing their traditional constituencies and some of them could be wooed by rival sides to bolster their strength.

Congress prays ahead of vote

On the other hand, the Opposition banks on the solid support of 169 National Democratic Allaince parliamentarians (BJP 130, Shiv Sena 12, Biju Janata Dal 11 and Janata Dal-United and Akali Dal -- eight each), 59 lawmakers of the Left parties and eight of the United National Progressive Alliance besides Bahujan Samaj Party with 17 members and a few others, taking the total to 263 -- still nine short of the magic mark.

The Telangana Rashtra Samiti, having three MPs, plans to oppose the government as it is unhappy with Congress for not carving out a separate state from Andhra Pradesh.

Muslim League to vote for N-deal

With the SP announcing its support to the government on the nuclear deal issue, arch-rival BSP may be expected to go against it. Reports have already appeared that Mayawati is trying to woo Samajwadi Party lawmakers and vice versa.

While refusing to divulge her strategy in the crucial trust vote, BSP supremo Mayawati has said Congress-led UPA should not be under any illusion that she will be 'intimidated'.

Efforts are also underway to rope in BSP in the UNPA fold after the exit of SP and Telugu Desam Party chief N Chandrababu Naidu [Images] was said to be lobbying with Mayawati in this regard.

While JD-S rebel member M P Veerenda Kumar has made up his mind to oppose the government, two JD-S MPs are yet to announce their decision.

The Deve Gowda camp is in touch with CPI-M to bring together 'secular' regional parties to act as a 'Third Front' after the UNPA fell into disarray with its biggest constituent SP parting ways.

As a BJP leader put it succinctly, confidence votes are tricky affairs and "we have learnt it the hard way in 1999. Had anyone expected that the Vajpayee government would loose by just one vote?