1968–1976: Creation and WP contests Potong Pasir Constituency was established prior to the
1968 general election; the PAP won uncontested. In the
1972 and
1976 general elections, the
Workers' Party (WP) challenged the PAP in the constituency, with the
United National Front (UNF) also doing so in 1972; all three challenges were unsuccessful. For not obtaining at least 12.5% of the vote, the UNF also lost their
electoral deposit of
S$500.
1979: By-election and entry of Chiam See Tong In 1979, as part of the
seven by-elections that year,
Chiam See Tong, future MP for Potong Pasir, contested the constituency as an independent candidate against PAP newcomer
Howe Yoon Chong. After submitting his nomination papers for the by-election, Howe dismissed opposition candidates as "court jesters" who had arrived "to provide comic relief". He went on to defeat Chiam with 66.85% of the vote, retaining Potong Pasir for the PAP.
1980: Formation of/first contest by SDP Ahead of the
1980 general election on 23 December, Chiam founded the
Singapore Democratic Party (SDP) in the same year and rematched against Howe in the constituency under the SDP banner. The party was formally registered on 8 September. In an election rally, Howe disparaged Chiam on his professional competence and was subsequently sued by Chiam for defamation. In response, Howe offered compensation which Chiam accepted; leading to the lawsuit being dropped.
1984–2011: Chiam era 1984–1996: SDP era During the
1984 general election, Chiam contested Potong Pasir for the SDP again. Howe retired from politics that year and did not stand for reelection; PAP newcomer
Mah Bow Tan was sent to retain the constituency. Leading up to the election, then-
Prime Minister Lee Kuan Yew compared Chiam and Mah's O-Level (
GCE Ordinary Level) results in a rally speech, saying, "Mah Bow Tan, age 16, took his O-Levels — six distinctions, two credits. Mr Chiam, age 18 — six credits, one pass." The
Prime Minister's Office later conveyed an apology from Lee for making an error about Chiam's results; Chiam had actually gotten seven credits. Chiam was elected MP for Potong Pasir after winning the election with 60.28% of the vote. In
1988, the constituency was renamed
Potong Pasir Single Member Constituency with the creation of
group representation constituencies (GRCs). Chiam retained his seat with an improved 63.13% of the vote against PAP candidate
Kenneth Chen Koon Lap. In
1991, Chiam won reelection with 69.64% of the vote against PAP candidate
Andy Gan.
1997–2011: SPP/SDA era In December 1996, when Parliament was dissolved ahead of the
1997 general election, Chiam left the SDP and joined the
Singapore People's Party (SPP), formed from a pro-Chiam former SDP faction which had left in 1994.
2001–2010: SDA era Prior to the
2001 general election, Chiam formed the
Singapore Democratic Alliance (SDA), a political coalition comprising his SPP and three other opposition parties. In said election, Chiam won reelection with 52.43% of the vote against
Sitoh Yih Pin, PAP newcomer and future MP for Potong Pasir SMC. In
2006, Chiam's vote share increased to 55.82% in a rematch.
2011: Withdrawal of SPP from SDA On 28 February 2011, prior to the general election in the same year, the SDA removed Chiam from his position as chairperson of the coalition. Subsequently, on 2 March, Chiam announced that he would withdraw the SPP from the SDA.
2015: PAP entrenchment In the
2015 general election, Sitoh retained his seat with 66.41% of the vote in a rematch against Loh, who did not return to Parliament. Sitoh defeated SPP candidate Jose Raymond with 60.67% of the vote, winning a third term in Potong Pasir SMC. On 22 April, the SPP announced that party treasurer Williamson Lee would contest the constituency. On nomination day,
Lim Tean, secretary-general of the
People's Alliance for Reform (PAR), a political coalition, was also nominated to contest the constituency, resulting in a three-way fight between the PAP, SPP and PAR. Yeo proceeded to win 69.2% of the vote against Lee's 22.46% and Lim's 8.33%; Lim lost his electoral deposit of $13,500 for not obtaining at least 12.5% of the vote. ==Member of Parliament==