Raffles Institution (RI) will be the focus of attention when nominations for the general election open today. All eyes will be on whether Workers' Party (WP) bigwigs Low Thia Khiang and Sylvia Lim will show up at the school - one of nine nomination centres - to keep their promise to defend Aljunied GRC.

The constituency, the opposition party's biggest scalp from the last general election in 2011, has lost some of its lustre, after financial lapses at its town council were uncovered by the Auditor-General's Office in February.

Political pundits are expecting a feisty contest in the GRC from a People's Action Party (PAP) team largely made up of newcomers but led by veteran MP Yeo Guat Kwang.

Mr Yeo has moved from Ang Mo Kio GRC, where Prime Minister Lee Hsien Loong and his team beat the Reform Party (RP) with 69.3 per cent of valid votes, the highest margin for the PAP in a GRC at GE2011.

Mr Lee and his team will also be filing their nomination papers at RI today, where they will face a new RP team led by activist lawyer M. Ravi and former client, blogger Roy Ngerng, who has been successfully sued by Mr Lee for defamation. The school in Bishan will also host candidates contesting Bishan-Toa Payoh GRC, where a PAP team helmed by Defence Minister Ng Eng Hen will face a five-man Singapore People's Party team.

The school in Bedok North will host candidates aspiring to contest Fengshan and Punggol East single seats as well as East Coast and Pasir Ris-Punggol GRCs.

Many are expecting a close fight for East Coast GRC where the PAP is sticking with its incumbents, who beat the WP by a whisker in the 2011 polls. The PAP team led by Manpower Minister Lim Swee Say will again face a strong challenge from a WP team hoping to prise another GRC from the ruling party.

The WP has yet to unveil its line-up for East Coast, but its team will largely feature new faces led by NCMP Gerald Giam.

Fengshan SMC, carved out from East Coast GRC for the polls, will also see a tough fight between the PAP and the WP for 23,404 votes. Both parties are fielding first-time candidates in the constituency.

Another hot seat is Punggol East SMC, where the incumbent Lee Li Lian from the WP will go up against veteran campaigner Charles Chong, redeployed by the PAP from Joo Chiat to win back the seat it lost in a 2013 by-election.

Another centre to watch is Bendemeer Primary, which will host candidates contesting Tanjong Pagar GRC, where the PAP enjoyed a walkover in 2011. This is the first time the constituency will not be contested by Singapore's founding Prime Minister Lee Kuan Yew, who died in March. He had represented the Tanjong Pagar area since 1955.

Assumption Pathway School may also be worth following as it will be where Dr Chee Soon Juan of the Singapore Democratic Party will likely make his return to politics. He was unable to contest the elections in 2006 and 2011 because of bankruptcy, but was cleared in 2012.

The coming polls will see all 89 seats contested for the first time since Independence and a bumper crop of candidates fielded.

The Elections Department said yesterday it had issued 220 political donation certificates, 35 certificates of the Malay community committee as well as 33 certificates of the Indian and other minority communities committee to applicants.

At least one candidate in 10 of the GRCs must be Malay, while at least one candidate in six of the GRCs must be Indian or from another minority community.

Police said that from today until Sept 17, candidates as well as those who are returned unopposed, or their election agents, may apply for police permits to conduct post-election vehicle processions to thank voters. There is a fee of $50 for the permit and applications can be made at the compliance management offices in various police divisional headquarters corresponding to the electoral divisions.