National parties want relentlessly to crush smaller and regional parties. They want to virtually eat them up in Bihar, Jharkhand, Uttar Pradesh and Maharashtra?. That was Lalu Prasad Yadav at the RJD?s national executive meet in Patna on November 4.

The sagging of Congress-RJD alliance talks for the upcoming Jharkhand polls formed the immediate context for Lalu?s remarks. But his words spoke of more than just that. They were tinged by the anxiety that seems to have gripped political parties, especially the caste- and community-based outfits, as they watch India?s voter fell enduring myths of impervious votebanks and immovable strongholds.

It would be no leap of the imagination to say that on Tuesday, Lalu?s words, or at least the panic that runs through them, touched off an uncomfortable echo for another Yadav chieftain who has just lost his pocket borough. On the day his daughter-in-law Dimple Yadav suffered a massive defeat at the hands of the Congress candidate in the by-poll in Firozabad ? part of UP?s Etawah-Etah-Mainpuri Yadav-dominated belt and in a seat that was vacated by her husband Akhilesh ? Mulayam Singh Yadav may also be nurturing the same sense of siege, and yes, even laying the blame at the same door.

Dimple Yadav?s rout in Firozabad is an arresting freezeframe in north Indian politics but perhaps it was not entirely unexpected. Aware of its shifting support base ? intimations of which had been served up by the BSP overtaking it in UP, and by the significant erosion of its core Muslim vote which had made it increasingly dependent on transient mobilisations of other castes, such as Lodhs ? SP had painted this by-poll in cataclysmic terms.

It was about its self-respect, its identity. ?This is about the SP?s maan, pratishtha? the whole nation is watching.? repeated Akhilesh Yadav, Mulayam?s son and party president in UP, during the campaign. ?SP needs your help?, he pleaded to Yadav voters in Shikohabad, with a humility rarely brought into play when a party talks to a vote-bank.

The SP was probably aware that if there was a message from the Lok Sabha polls earlier this year, it was this: Regional parties are not in decline and there is no surge in fortunes of the national parties, but something is definitely changing. Caste and community remain the primary building blocks of political loyalties at ground level, but the politics of building political coalitions based on these may have started delivering diminishing returns.

This was evident in the standstill reached by the electoral fortunes of parties like the RJD, SP, PMK and BSP. Parties which depend on a single caste for the bulk of their votes, political analysts Suhas Palshikar and Yogendra Yadav wrote in their analysis of the 2009 LS results in the Economic and Political Weekly, have discovered that there is little scope for making further gains. ?They have also discovered that secondary alliances built by them ? with Muslims in the case of the RJD and SP and with Brahmins in the case of the BSP ? prove short-lived?.

And as the traditionally ?catch-all? party ? as imperfect as that image may have proved to be in practice ? the Congress is reaping the benefits of wider political shifts it has done nothing to bring about.

In UP, for instance, the story of Congress revival in the May 2009 LS polls was made up of the shrinking base of all other parties. The Congress was the only party in UP to register a vote swing in its favour from every caste and community; the SP, BSP and BJP all registered negative swings away from them in several groups ? the two movements were related.

According to the National Election Study 2009 conducted by the CSDS, compared to 2007, the gains for the Congress came from upper castes, upper OBCs (except Yadavs), Dalits (except Jatavs) and Muslims. Gains among upper castes came at the cost of the SP and the BSP, Lodh votes came at the cost of the BJP, while gains among Kurmi-Koeri voters came at the cost of all other parties. Major gains among Muslims came at the cost of the SP.

For the SP, Muslim vote had shrunk from 79% in 1996 to 47% in 2004. Between assembly polls 2007 to Lok Sabha polls 2009, there was a further swing of ? 16.7 percentage points away from the SP.

The humbling of the SP in its backyard in these by-polls appears to carry forward the trend of the upsetting of previously unassailable votebanks ? with a difference. In the May 2009 polls, while all non-Congress parties lost votes to the Congress, they gained in their core constituencies. The SP may have lost among Muslims but it gained among Yadavs, and the BSP gained among Dalits.

Does the defeat of Dimple Yadav in a constituency in which the Yadavs are the single largest slice of the electorate suggest that Yadav support for Netaji?s party is cracking as well? The answer will be consequential for the politics of the future ? in UP as well as in India.