KUALA LUMPUR, March 30 -- The by-election for the Rantau state seat, which kicks off today, has been billed as the "mother of all elections" and that could very well be the case with the country's two major political coalitions jostling to make a statement.

It will be an important performance yardstick for both Barisan Nasional (BN) and Pakatan Harapan (PH) to gauge voters acceptance of them in their current role as the Opposition and the ruling coalition respectively.

Voter sentiment has swung between PH and BN in the 10 months since the former took over the government.

Though PH enjoyed an arguably smooth ride in the first few by-elections immediately after it assumed the mantle in Putrajaya, the euphoria of its May 9 victory has bee...