Beneath the BJP’s high-pitched outrage against Jharkhand Governor Syed Sibtey Razi’s ‘‘brazen assault on democracy’’, there is quiet jubilation in party circles since the spin-off effect could cause grave damage to the UPA and revive the NDA’s sagging spirit.

‘‘We may have lost the chance to form a government in Ranchi, but we have finally got an effective weapon against the Congress,’’ a BJP leader said, echoing not only the sentiments of NDA constituents but the quiet rumblings within the UPA and even Congress.

The decision to swear in JMM chief Shibu Soren today on the basis of his list of 42 MLAs as opposed to the BJP-JDU’s 41 MLAs is being portrayed as a return to old Congress tactics of misusing the office of Governor. In light of the Goa imbroglio and reports that Bihar Governor Buta Singh may also swear in Rabri Devi soon, the BJP has found enough ammunition to attack the Congress’ ‘‘anti-democratic’’ tendency.

The events in Jharkhand, NDA leaders feel, will help them in at least four ways. First, it will damage the credibility of both Sonia Gandhi and Manmohan Singh as upholders of principled politics. The BJP’s efforts in that direction have so far proved futile. Despite constant propaganda against the ‘‘super PM’’, Sonia has retained the goodwill she acquired by her ‘‘sacrifice’’ in May. Manmohan, too, has been a hit, particularly with the middle class. But the revival of the ‘‘discredited 1970s era tactics’’ could once again alienate the middle class.

Second, the Congress moves could cause fissures in the UPA in the long run. ‘‘The Congress does not know how to handle coalitions. In Bihar, when they should have supported Laloo, they opposed him. And now when they should oppose him, they are supporting him,’’ a JDU leader said. With UPA partners already miffed with the Congress over Maharashtra and Bihar, the ‘‘misuse’’ of Governors can only make partners even more wary, they feel.

Third, the action will help cement unity in the NDA. ‘‘Sections in the JDU have been working to break ties with the BJP and join a secular combine in Bihar if such a realignment becomes possible, but the Congress has only strengthened JDU-BJP ties with its actions in Jharkhand and Bihar,’’ a source said.

And fourth, it might have a direct fallout in Bihar. Sections in BJP feel that if Rabri Devi is sworn in and fails to win a vote of confidence, Ram Vilas Paswan might join hands with the NDA. ‘‘The Congress decision to support Rabri’s claim is a slap on the face of Paswan. It will be much easier for us to work on him,’’ an NDA member said.

The NDA is set to go full throttle both inside and outside Parliament. BJP president L.K. Advani said the Governor’s action reminded him of the Emergency era. He also led an NDA delegation to Rashtrapati Bhavan asking the President to intervene.

Advani brushed aside reminders that during the NDA rule too, the then Bihar Governor had invited Nitish Kumar to form the government even though the JDU-BJP had one less MLA than the RJD. ‘‘Why should we talk of 2000 in 2005?’’ he said, while asserting that under NDA all Governors had been appointed after ‘‘consultation’’ and with the ‘‘concurrence’’ of chief ministers.