Pakatan Harapan reneging on its promises is one of the reasons it failed to retain the Semenyih state seat, according to senator Khairul Azwan Harun.
The Umno leader also listed other factors which he believes contributed to Harapan's electoral loss in yesterday's polls, such as fielding the wrong candidate.
"From day one, Harapan candidate (Muhammad Aiman Zainali) made mistakes, showed his inexperience.
"He talked about building a hospital, when our surveys showed voters were more worried about traffic congestion, overdevelopment and water disruption... major local municipal issues," he said in a statement today.
Khairul Azwan also pinned the defeat on the Selangor government's "overconfident promises."
These, he said, reminded voters of Harapan's unfulfilled pledges from the 14th general election.
"Harapan has ruled Selangor for more than two terms now, but it has continued to ignore local issues – leading to massive protest votes.
"The cost of living has also not improved. Harapan's excuse of needing more time is getting old."
Khairul Azwan cited as examples Putrajaya's decision to float fuel prices – despite earlier promising to stabilise it – and prices of goods not falling despite the reintroduction of SST.
The senator alleged that Harapan employed "dirty tactics" in its by-election campaign, such as with handouts of cash and hampers, which reminded voters that the coalition is "not clean."
He also cautioned that BN should stay grounded despite the electoral win, stressing that the main determinant of an electoral victory is socioeconomic issues.
BN's Zakari Hanafi won the Semenyih by-election yesterday, with 19,780 votes to Aiman's 17,866.
PSM's Nik Aziz Afiq Abdul and independent Kuan Chee Heng polled with 847 and 725 votes respectively.