On one side is 81-year-old L.K. Advani, whom the Hindu nationalist party had announced as its prime ministerial candidate almost a year ago.

On the other is 85-year-old Bhairon Singh Shekhwat, a veteran leader and former Indian vice-president who recently emerged from retirement to announce his decision to contest the parliamentary elections.

His move is not only seen as a direct challenge to Mr Advani's bid for prime ministership, but also as a revolt against the party leadership.

Coming just ahead of the national election expected in May, the leadership squabble and other debilitating dissensions are hobbling the party as it prepares to go to the polls. This revives faint hopes in the Congress party-led ruling coalition of returning to power this year.

'Factionalism has always been a problem within the BJP,' said Prof Sudha Pai from the Centre for Political Studies at New Delhi's Jawaharlal Nehru University.

'There are too many ambitious leaders in the party, each trying to pull down the others.'

Indeed, the BJP, which was first off the block in the electoral race to announce Mr Advani's candidacy, appears to have lost the script in recent months.

Analysts link its current problems to the unexpected reversals the party had suffered in the recent elections for six state assemblies.

The BJP was riding high on a string of electoral victories in the past three years, but managed to win in only two of the six states that went to the polls. Most importantly, it lost the prestigious Delhi state assembly elections against all expectations.

The losses quickly prompted rumblings of discontentment within the party, with veteran leader and former minister Murli Manohar Joshi - a known rival of Mr Advani - publicly criticising the way the election campaign was run.

Others blamed the losses on the party's inability to curb factionalism within its ranks, with BJP spokesman Prakash Javdekar citing it as the cause of its loss of power in a large state like Rajasthan.

The latest blow to hit the prime ministerial candidate is Mr Shekhwat's announcement, which some see as further evidence of factionalism.

BJP leaders had attempted to dissuade the veteran leader from entering the electoral fray, pointing out that former presidents and vice-presidents usually kept away from the political arena, but Mr Shekhwat had brushed them aside.

One party insider noted that while Mr Shekhwat's move was 'not a serious threat' to Mr Advani, it reflected the BJP's internal fissures.

'It's more of a nuisance, but it reinforces the BJP's image as a divided house ahead of elections,' he said.

But analysts say it is too early to write off the BJP.

Congress, noted analyst G.V.L. Narasimha Rao, had found itself in a similar situation before the previous parliamentary elections in 2000, but managed to come out on top.

'The BJP lost at that time because of overconfidence, but it could still turn the table on the Congress by getting its act together,' he said.

pjay@sph.com.sg