With the Singapore Democratic Party’s (SDP) 6th April 2025 announcement of its Sembawang GRC slate (L-R: Damanhuri Abas, Dr. James Gomez, Bryan Lim Boon Heng, Surayah Akbar, and Alfred Tan), the outline of its “Northern Strategy” is complete.
Both Sembawang GRC and the embedded Sembawang West SMC led by SDP’s chief Dr. Chee Soon Juan (CSJ) are expected to strongly synergise their campaigns which is likely to create a ripple knock-on effect onto Marsiling-Yew Tee GRC.
Sembawang GRC was formed as a 5-member GRC in 1988 when the GRC system was first established. It was contested then for the first time by the United People’s Front, which polled 29.9% (15,436 voters) out of 51,590 total votes cast. It was left uncontested in GE1991, GE1997 and GE2001 yielding a walkover to the People’s Action Party (PAP) until the SDP contested in 2006.
Sembawang GRC saw an exponential growth in geographical size across GE1988, GE1991 and GE1997. In GE1997, Bukit Panjang SMC was added to Sembawang GRC and was upsized from a 5 to 6-member ward.
In 2001, part of Sembawang GRC were taken out since a portion of the original Bukit Panjang SMC was carved out and appended to newly formed Holland-Bukit Timah GRC, alongside the Ulu Pandan divisions of Bukit Timah GRC and Buona Vista divisions of Tanjong Pagar GRC. Nee Soon East was additionally carved out to form its own SMC.
In GE2006, Sembawang GRC’s geographical size stayed roughly the same size with a part of Yishun carved out to join Nee Soon South SMC.
Meanwhile, the voter size of Sembawang GRC saw a huge increase. The number of electors that was 55,633 in GE1988 grew to 117,951 in GE1991, to 154,402 in GE1997 before reaching 166,137 in GE2001. In GE2006, it ballooned to a record 184, 804.
In contrast, since 2011, there has been a decrease in the geographical size of Sembawang GRC. In 2011, it was downsized from a 6-member constituency to a 5-member one. It has remained a 5-member GRC ever since.
In 2011, a large swathe was carved out to form Nee Soon GRC. In 2015, another section was merged into Marsiling-Yew Tee GRC, and some areas were added from Nee Soon GRC into Sembawang GRC. In 2020, portions of Sembawang GRC were taken into Marsiling-Yew Tee and Nee Soon GRCs.
The voter numbers also broadly decreased with slight fluctuations. In GE2006, the number of electors for Sembawang GRC was highest at 184,804. This dropped to 142,459 in GE2011 due to the downsize, before climbing slightly in GE2015 to 144,672 and in GE2020’s increasing slightly to 147,876.
This year (2025), Sembawang West was carved out from Sembawang GRC to create a new SMC of 24,192 eligible voters. With that, the voter size for Sembawang GRC has dropped to an all-time low of 134,103 eligible voters.
Dr. Gomez is the only returning nominee from SDP’s 2011 Sembawang GRC slate. Notably, he was part of the GE2011 team that pulled away 12.8% from the ruling party’s GE2006 vote shares, increasing SDP’s vote share from 23.3% (39,537 voters) in 2006 to 36.1% (47,605 voters).
In 2011, Sembawang GRC also recorded the biggest GRC swing of that election year, and it is SDP’s largest GRC swing to date since GE2011. Since GE2011, no opposition in Sembawang GRC has obtained a vote share surpassing that of SDP’s GE2011’s results.
To win over Sembawang GRC in GE2025, SDP would require a minimum of 50.1% (or 67,185 voters assuming all votes are valid) of the vote share.
Indicatively, this result would require pulling, in SDP’s favour, either a 14% (based on GE2011 results) or 17.39% swing (based on GE2020 results). Both swing sizes are attainable targets, as demonstrated by the Progress Singapore Party’s (PSP) in GE2020 – it obtained the following percentages swing in its favour: at Tanjong Pagar GRC, 14.58%; at Chua Chu Kang GRC, 18.25%; and at West Coast GRC a 26.89% swing in its favour.
In the SDP’s case, is this swing and a win even possible – that is the question for discussion.
Unlike in previous elections, this time Sembawang West SMC is embedded within the Sembawang GRC, and this is likely to benefit from the Chee Soon Juan (CSJ) effect.
So what is the CSJ effect?
Drawing from statistics in the last ten year period, when Dr. Chee Soon Juan first contested in the 2016 by-elections for Bukit Batok SMC, he polled 38.77% (9,150 voters) of 25,727 electors, pulling away an impressive 12.39% from the incumbent’s vote share. Following this achievement, in GE2020, Dr. Chee proceeded to pull away an additional 6.43% from the same incumbent, polling 45.20% (12,787 voters) of 29,948 electors.
This knock-on effect, called the CSJ effect, is expected to add bounce not only to Sembawang GRC but ripple onto Marsiling-Yew Tee GRC.
There is also the additional element of moving SDP candidates who had previously contested in Marsiling-Yew Tee GRC to Sembawang GRC to establish cross-connection between party members and volunteers from the two GRCs. It is important to note, it’s a matter of public record that the SDP had announced and began walkabouts in Sembawang GRC in 2022 as an extension of its ground operations and presence in Marsiling-Yew Tee GRC.
SDP’s GE2025 Sembawang GRC slate connects the dots and fully contours the SDP’s “Northern Strategy”. It stands electorally firm in Singapore’s Northern Front.
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