During the March 1960 Ceylonese parliamentary elections, the MEP obtained 10 parliamentary seats. In the 1960s the group joined with the Lanka Sama Samaja Party and the Communist Party of Sri Lanka to form the United Left Front. On September 29, 1963, 800 delegates, representing a million workers, ratified a charter of 21 demands that sought to encapsulate the demands and goals of Sri Lankan workers.[1]
National Government the United National Party
In 1965, the party joined hands with Prime MinisterDudley Senanayake of the United National Party to form a national government under Senanayake's leadership. During this time, Philip Gunawardena was appointed as a cabinet minister.
Under Dinesh Gunawardana
Following his father's death in 1972, Dinesh Gunawardena became the new leader of the MEP. In 1983, Dinesh Gunawardena became the common candidate to contest in the Maharagama by-election under the MEP's symbol, a cartwheel, in which he won with an overwhelming majority to become one of the 8 members of the opposition in the Sri Lankan Parliament.
In 1989, the MEP contested alone under the new proportional representation electoral system and won only 3 parliamentary seats out of 225, with Dinesh Gunawardena MP for Colombo District, Bandula Gunawardane MP for Colombo District and Gitanjana Gunawardena as a National List MP.
In 2000, the MEP became one of the constituent members of the Peoples' Alliance, a political alliance led by the SLFP, where the MEP had 3 representatives in Parliament (Dinesh Gunawardena, Bandula Gunawardena and Somaweera Chandrasiri).
In the 2004 Sri Lankan parliamentary elections, the party was part of the United People's Freedom Alliance, which won 45.6% of the popular vote and 105 out of 225 seats. There were two MEP representatives in the parliament including one National List MP. The two representatives were Minister of Urban Development and Sacred Areas Development and Chief Government Whip Dinesh Gunawardena and Housing Minister Gitanjana Gunawardena.
In the 2010 Sri Lankan parliamentary elections, the UPFA won nearly two-thirds of the Parliament, with 143 out of 225 seats. There were three MEP representatives in the parliament including one National List MP. The three representatives were Minister of Water Supply and Chief Government Whip Dinesh Gunawardena, Deputy Foreign Minister Gitanjana Gunawardena, and Lady member Sriyani Wijewickrama.
In the 2015 Sri Lankan parliamentary elections, the UPFA was in opposition the Parliament, with 104 out of 225 seats. There were three MEP representatives in the parliament, including Joint Opposition Leader Dinesh Gunawardena and Sriyani Wijewickrama.
In 2019, the MEP joined the Sri Lanka People's Freedom Alliance, led by former president Mahinda Rajapaksa. In the 2020 Sri Lankan parliamentary elections, the SLFPA won a landslide victory, winning 145 out of 225 seats of the Parliament.
