Several political analysts have been predicting that it will be difficult for the Singapore Democratic Party (SDP) to win the Bukit Batok single-member constituency (SMC) due to the following two reasons:

1. Huge vote swing needed against the People's Action Party (PAP):

With former MP David Ong scoring 72.99% in General Election 2015, SDP's Chee Soon Juan will need at least a 23.7% vote swing against PAP to win.

In other words, this translates to about 5,885 voters in Bukit Batok switching their vote from PAP to SDP this by-election.

Take PAP's Punggol East by-election loss in 2013 as an example and the swing against the PAP was 10.81%.

In other words, 4,119 PAP voters decided to vote for Workers' Party (WP), Reform Party or Singapore Democratic Alliance instead.

2. Short time frame since the last GE:

If the by-election is called this May, it would have been just eight months since the last GE.

Surely things in the constituency haven't changed so much during those eight months?

Anson SMC by-election showed huge swing possible

Except that one cannot predict the votes of the people by logic, mathematical models or time frames alone.

Let's go back to four by-elections ago: Anson SMC in 1981.

In the 1980 GE, then PAP MP Devan Nair -- who went on to become Singapore's third President -- scored an impressive 84.1% of votes, or 11,564 votes in total.

A mere 11 months later, the PAP suffered a 37% swing against them and lost its first parliamentary seat since Singapore's independence.

J.B. Jeyaretnam, running on a WP ticket, won decisively against the insurmountable odds, by receiving 7,012 votes, or 51.9 percent.

The PAP candidate, Pang Kim Hin, got 6,359 votes, or 47.1 percent.

In an interview for the Men in White (2009) book, Emeritus Senior Minister (ESM) Goh Chok Tong, who was in charge of that 1981 BE campaign, acknowledged that he "was too mathematical and logical in his approach to fighting the by-election".

Goh who could not imagine the vote going down to less than 50 percent in just 11 months, said:

"That's the real lesson of politics...Don't assume the last votes will not change too drastically. The ground can turn, depending on the issues and how the candidates campaign".

Of course, a by-election doesn't take place in a vacuum.

Context is important as there were factors working against the PAP at that time, in particular, simmering discontent experienced by the public over government decisions and policies, and the fact that the PAP candidate was a political novice who alienated his grassroots leaders.

We can wait with bated breath.

Related articles:

5 observations of how the PAP will tackle the “Chee by-election” in Bukit Batok

Confirmed: PAP fields ex-Aljunied candidate Murali Pillai for Bukit Batok by-election

Lianhe Zaobao: Murali likely to contest in Bukit Batok by-election

How about Murali Pillai, 47, as PAP’s candidate for Bukit Batok SMC by-election?

Top photo from National Archives of Singapore.

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