The Left Democratic Front (LDF) bagged an extra four seats in the local body byelections, pushing its tally to 24 seats.
When the byelection results for 42 wards were out on Wednesday, the United Democratic Front (UDF) seat share had marginally dwindled from 15 to 12.
The Bharatiya Janata Party (BJP) saved face by bagging six seats.
The CPI(M) calculates that the marginal increase in its seat tally might be bellwether of beneficial voting behaviour in the upcoming Thrikkakara Assembly byelection on May 31.
However, the LDF's loss of a simple majority in the Tripunithura Municipal Corporation dampened the ruling coalition's triumphal spirit.
The BJP's victory in two wards in the local body has arguably thrown cold water on the CPI(M) 's confidence.
The ruling front appeared concerned that its campaign could not make the desired impact among voters in the Ernakulam district.
The CPI(M) could take some consolation that the party had managed to wrest a local body ward from Congress in the Kunnathunad panchayat reckoned as a stronghold of the Twenty20 outfit in Ernakulam.
Congress had cast the Twenty20's tactical withdrawal from the Thrikkakara Assembly bypoll as a tactical win for the UDF.
The CPI (M) also viewed the loss of the Velliyanoor panchayat in Kollam to the UDF as a setback.
The BJP could pat itself on the back to retain the Ernakulam South ward in the Thrikkakara Assembly segment and capture two seats in Tripunithura Municipality from the CPI(M).
The byelection results, which buoyed the LDF's self-assurance to a limited degree, have come on the eve of the second Pinarayi Vijayan's completion of 100 days in power.
Chief Minister Pinarayi Vijayan attributed the results to the LDF's welfare and development programme.
He said they were also a firm warning against the anti-development and divisive agenda of Congress and BJP.
CPI(M) State secretariat said voters had rejected that UDF-BJP "rainbow coalition" forged in the smithy of political opportunism. They had aligned themselves with the LDF's development platform.
Despite the local body results, the Thrikkakara Assembly byelections remained a toss-up between CPI(M) and Congress.
Mr. Vijayan has predicted voters would elevate the LDF's tally in the Assembly from 99 to 100. He has also cast the election as a yardstick of public approval for the LDF's development agenda, chiefly K-Rail.
