Patna, Oct 5 (IANS) Whichever way one looks at it, Rashtriya Janata Dal (RJD) chief Lalu Prasad, jailed for five years for siphoning off government money, will remain a strong influence on the politics of Bihar.

With Lalu Prasad behind the bars, his rivals are eyeing inroads into his traditional social support base, while the RJD hopes to benefit from the sympathy factor to ensure its support base remains intact.

Lalu Prasad's importance can be gauged from the manner in which his main rivals BJP and JD-U, in hoping for support from his Yadav caste, have chosen against targeting him after his conviction in the fodder scam to avoid antagonising the Yadavs, who constitute more than 11 percent of Bihar's 105 million population.

Yadavs are considered not only loyal to Lalu Prasad but is also a strong force to counter upper caste dominance in state politics in the last over two decades.

Sensing trouble for Lalu Prasad in the fodder scam case, the BJP appointed a Yadav, Nand Kishore Yadav, as leader of the opposition in the state assembly after JD-U ended its 17-year-old alliance with it in June.

"It was a calculated move to project him to influence the Yadavs, who may be in a dilemma after Lalu Prasad was jailed and there appears to be a leadership vaccum in the RJD. The BJP will exploit this factor to widen its support base among those of Lalu Prasad's caste," a BJP leader said.

In the caste-driven politics of Bihar, the BJP is well aware that other backward castes like Kurmis to which Chief Minister Nitish Kumar belongs, are solidly behind him while the Koeris are not behind any single political party or leader.

Till date, the BJP is seen as a party that enjoys overwhelming support of the upper castes and backward castes like Baniyas.

"The BJP will try to eat into Lalu Prasad's support base but it will not be an easy task," another BJP leader said.

But JD-U MP Shivanand Tiwari, who was once close to Lalu Prasad, said the Yadavs will not ditch the jailed leader in his hour of crisis. "Lalu's castemen will come out in support of him to express their sympathy," he said.

RJD MP Ram Kirpal Yadav said that in this time of crisis, "the party is united and intact". Lalu Prasad is the soul of the RJD and his popularity will now increase among his traditional supporters," Kirpal Yadav said.

RJD activists fear that the Congress will now happily dump the RJD and go with Nitish Kumar's Janata Dal-United (JD-U).

JD-U leaders hope that Muslims, who constitute 16.5 percent of the population, will now be attracted towards the party, in part because of the BJP's prime ministerial candidate Narendra Modi.

"It is a fact that Nitish Kumar dumped BJP over Modi and that will help the party gain more support among Muslims," JD-U leader Sanjay Singh said.

BJP and JD-U leaders had repeatedly claimed that Lalu Prasad's vote bank was already shattered and this was evident during the 2010 assembly elections and the 2009 Lok Sabha polls.