Shortly before the counting of votes in Kerala’s Aruvikkara assembly by-election, Communist Party of India-Marxist (CPM) state secretary Kodiyeri Balakrishnan make the startling claim that the entry into the contest of veteran Bharatiya Janata Party (BJP) leader O Rajagopalan had made it difficult for his party to unseat the incumbent Indian National Congress (INC).

He was right. The INC (or rather, the INC-led United Democratic Front) won 40% of votes cast, the same percentage as it had in the 2014 general election. The CPM-led Left Democratic Front that had won 43% of the vote in 2014 got only 33% this time. The BJP’s tally however doubled from 12% to 24%, with most of the gains coming from the CPM, which ensured the INC’s victory. Had the voting pattern of the general election been repeated, the CPM would have triumphed over the INC.

BJP supporters were naturally jubilant.

Still, it may be a bit early to pop the gau-champagne. The BJP’s Rajagopalan is one of a handful of credible leaders in the party’s state unit, and had previously given a tough fight to the INC’s Shashi Tharoor in Thiruvananthapuram in 2014. It remains to be seen whether this result is a flash in the pan, or the start of a bigger shift in votes towards the BJP.

A real shift could well facilitate the UDF’s reelection in 2016, as the BJP’s rise divides the opposition vote statewide. As the following chart shows, Hindu voters have long leaned towards the LDF in Kerala, while Muslim and Christian voters have coalesced around the UDF.

If the BJP continues to gain support among, for instance, Ezhava voters, it could fragment the LDF’s vote base even as the latter attempts to take advantage of any anti-incumbency against the UDF. In both Kerala and West Bengal, the rise of the BJP is posing a severe challenge for the CPM and its allies.

Update on Jul 1

On reflection, it would appear that the Aruvikkara result has little to say about the BJP’s wider prospects in Kerala. Click here for why.