A number of factors including perceptions of Economy Minister Rafizi Ramli, the recent hike in diesel price, concerns over a similar increase in petrol price as well as the BlackRock controversy may come together to make a Pakatan Harapan (PH) victory in the Sungai Bakap by-election tomorrow a near-impossible feat.

There is also the minimum threshold of Malay support that PH will need to win – at least 15%, according to analysts who say this will be difficult for the coalition to achieve.

Malay voters, by and large, have supported Perikatan Nasional (PN) since the last general election two years ago.

Mazlan Ali of Universiti Teknologi Mara said PAS, meanwhile, which is representing PN in Sungai Bakap, will not have to rely on non-Malay support to retain the seat.

"For PH, the non-Malay votes are not a problem, and it is not a problem for PAS if it does not get the non-Malay votes as the Malay votes are enough," he said.

Malay voters make up 59% of the 39,222 voters in Sungai Bakap, which is part of the Nibong Tebal federal constituency represented by Education Minister Fadhlina Siddiq.

Chinese voters make up 22.5% and Indians 17.4%.

PH is fielding Joohari Ariffin of PKR while PN is represented by Abidin Ismail, both locals.

Mazlan said the situation in Sungai Bakap would mirror that of the by-election in Kuala Kubu Baharu in May, only in favour of PN this time.

In Kuala Kubu Baharu, PN's loss was attributed to his lack of support from the non-Malay voters. In Sungai Bakap, on the other hand, PH will need a significant proportion of the Malay vote to win.

"In Sungai Bakap, the Malay vote will be crucial as both parties are trying to woo them," Mazlan said.

PN campaigners appear generally happy with the trend of support for the opposition coalition.

A PH worker who has been following the campaign, however, said the coalition was still "struggling" to win over the Malays.

Efforts were further complicated by an incident early in the campaign period where Rafizi became involved in an argument with a man in an Umno shirt who questioned the fuel price hike.

"They (Umno members) are not happy when they see Umno members being treated badly by the unity government ministers," said one of PH's campaigners.

Rafizi, who is leading the PH campaign, has said that victory is certain for the ruling coalition. He also expressed confidence that the Malays would support the government.

"When we asked voters if they are satisfied with PN's performance over the past year, we expected 70% to support it, but only 48% are satisfied.

"Malay voters have not been satisfied since PN took over the state seat. And the Chinese and Indian voters, of course, are even more dissatisfied," Rafizi said during one of his campaign speeches.

However, Indian voters appear to have been increasingly vocal about their dissatisfaction with Prime Minister Anwar Ibrahim, as was the case in Kuala Kubu Baharu.

"Indian voters are dissatisfied and are increasingly feeling the pressure from the cost of living, as well as issues such as development and unfair treatment," said Suthan Mookaiah, spokesman for the Malaysian Indian People's Party which has been actively campaigning in Sungai Bakap over the past weeks.