The Congress-led UDF appears to be losing ground in Kerala to its main rival, the LDF led by the CPI-M.
Of 20 seats for which trends are available, the LDF is ahead in 18.
The two seats where the UDF leads are Ponnani, where Indian Union Muslim League general secretary E Ahmed is the party candidate, and Mavelikkara, where AICC secretary Ramesh Chennithala battles CS Sujata of the CPI-M.
Janata Dal (S) stalwart M P Veerendrakumar has established a comfortable lead of over 12,000 votes in Kozhikode over V Balram (INC).
In a surprise development, the IUML's KPA Majeed is trailing in Manjery by over 10,000 votes to T K Hamsa of the CPI-M.
In a triangular battle in Thiruvananthapuram, former Chief Minister P K Vasudevan Nair (CPI) is leading over Union Minister O Rajagopal; sitting MP VS Sivakumar of the Congress is in third place.
In other trends, Dr Sebastian Paul (LDF) leads Edward Edezhath (INC) in Ernakulam; in Muvattupzuha, the CPM's P M Ismail has a slender 78 vote lead over P C Thomas (IFDP).
In Palakaad, N N Krishnadas (CPM) leads V S Vijayaraghavan (INC); Mullapally Ramachandran (INC) is ahead of the CPM's AP Abdulla in Kannur; and in Badakara, P Sathidevi of the CPM is leading the INC's MT Padma.
In Ponnani, E Ahmed of the MUL is ahead of P S Suneer of the CPI while in Idukki, Francis George (KEC) leads Benny Behnann (INC). In Chirayinikil, MI Shanawas of the INC trails Varkala Radhakrishnan (CPM).
In a rude shock to the A K Antony government, meanwhile, state electricity minister K Muraleedharan, son of senior Congress leader K Karunakaran, is trailing his CPM rival A C Moideen in the Wadakkanchery assembly seat by-election.
The by-election was necessitated by Muraleedharan's induction into the Antony cabinet, three months earlier, as part of a patch-up scheme in the faction-riven Congress.
In a double blow to the veteran leader, Karunakaran's daughter Padmaja Venugopal is trailing well behind the CPM's Lonappan Nambadan in Mukundapuram Lok Sabha seat.