On Wednesday, the DMK and Congress sealed a pre-poll alliance for the 2019 general elections. According to the announcement made by DMK president MK Stalin, the Congress will contest on nine seats in Tamil Nadu and the one seat in Puducherry, while the DMK will share 30 seats with other potential allies like the MDMK and VCK.

The announcement came close on the heels of the BJP and the ruling AIADMK sealing an alliance in both Tamil Nadu and Puducherry. Announced by deputy chief minister O Panneerselvam and BJP’s Tamil Nadu in-charge Piyush Goyal, the “mega alliance” will also include the Pattali Makkal Katchi (PMK).

The PMK has held about 15-20% of the vote share in north Tamil Nadu and about 6-7% in Tamil Nadu as a whole for the past 20 years. The party’s alliances though, have moved across the spectrum over the years. In 2004, it aligned with the DMK and the Congress; in 2009 it aligned with the AIADMK as part of the third front, and in 2014 it again aligned with the DMK and the Congress.

Overall, the AIADMK-BJP-PMK alliance provides for five seats for the BJP and seven seats for the PMK, one in Puducherry. Sources have said that the AIADMK will hold about 22-25 seats and smaller regional parties will contest about three seats either on an AIADMK or a BJP ticket considering the state-wide and national-level appeal that the parties hold. And in the context of smaller regional parties in Tamil Nadu, symbols of larger parties — the two leaves (AIADMK), the rising sun (DMK), the lotus (BJP) — could go a long way in influencing voting patterns.

The other key regional player is the DMDK, which, sources said, is currently being wooed by both the AIADMK-led alliance and the DMK-led one. A final seat-share pattern in both the alliances should be sorted depending on which way the DMDK leans.

An important aspect of the announcement is the fact that the three-party alliance has also joined hands for the bypolls in 21 Assembly seats that are set to coincide with the dates of the general elections.

The 21-seat vacancy was created in the Assembly when 18 MLAs were disqualified under the anti-defection law; two MLAs — M Karunanidhi and AIADMK’s AK Bose — died; and Balakrishna Reddy, the MLA from Hosur, resigned on being convicted in a 1998 arson case.

The Assembly election is especially crucial for the AIADMK since its majority is at stake. The party has to win at least eight of the 21 seats to retain majority and survive till 2021, when the state goes to the polls. And it is largely eyeing support for the Assembly elections that the AIADMK aligned with the BJP for the 2019 polls.

The DMK-Congress, however, are yet to confirm if their alliance also stands for the bypolls.

Both the elections are crucial for the state which has lost two key political figures since 2014 — Jayalalithaa and Karunanidhi. It would also be of interest to note voting trends in view of the fact that the AIADMK has been in disarray since the passing away of Jayalalithaa.

In 2014, the Jayalalithaa-led AIADMK contested on its own and won a historic 37 of 39 seats, while prominent candidates like DMK’s Dayanidhi Maran and A Raja, and Congress’ Karti Chidambaram lost in their respective constituencies. But now, without the strength of a Jayalalithaa-led AIADMK, the party has had to resort to outside support.

As for the DMK and the Congress, neither won a single seat in the 2014 elections.