The People's Action Party (PAP) team led by Deputy Prime Minister Heng Swee Keat has retained East Coast GRC with 53.41 per cent of the votes.
The PAP's vote share is down from 2015, when it won 60.73 per cent. Both times, it claimed victory against a team from the Workers' Party (WP).
The contest this time was closely watched as the WP had fielded some of its stronger teams there since first mounting a challenge to the ruling party in the 2006 General Election.
Mr Heng thanked voters for braving the long queues and hot sun to cast their votes.
"My team and I thank you for your trust and support for us. With your mandate, we are determined to serve you better and to emerge stronger from this global pandemic," said Mr Heng, who also thanked the WP for giving his team a "strong contest".
Mr Heng's surprise move to helm the PAP's East Coast team on Nomination Day significantly strengthened the PAP slate. The 59-year-old moved over from Tampines GRC, to replace former minister and labour chief Lim Swee Say, who has retired from politics.
One of the hallmarks of Mr Heng's political style is an emphasis on consultation and conversation.
He entered politics in 2011 after 27 years in the public service. In 2012, when he was education minister, Mr Heng launched the Our Singapore Conversation series to get Singaporeans talking about the kind of country they want to build for the future.
He was appointed deputy prime minister in May last year and as the PAP's first assistant secretary-general, is No. 2 in both the Cabinet and the ruling party.
A year ago, he detailed plans on how the fourth-generation political leadership team aims to work with Singaporeans in a movement they are calling Singapore Together.
And on the last day of the campaigning period, he unveiled plans for a new East Coast Conversation series for residents to talk about the issues they care about.
Much of his time at the hustings was spent getting to know residents in the GRC with 121,772 registered voters. On top of his house visits, Mr Heng has visited most major markets and food centres in East Coast GRC at least twice during the campaigning period.
Apart from Mr Heng, the PAP's five-member team in East Coast comprises Senior Minister of State for Defence and Foreign Affairs Maliki Osman, 54; Ms Jessica Tan, 54; Ms Cheryl Chan, 44; and new face Tan Kiat How, 43. Mr Tan was formerly chief executive of the Infocomm Media Development Authority before he resigned last month to enter politics.
They were up against a WP team led by lawyer Terence Tan, 49, the WP's deputy organising secretary, and which included Ms Nicole Seah, 33. She was the National Solidarity Party's star candidate in the 2011 election.
After the results were announced, Ms Seah thanked voters for their support. "We went into this knowing that it was going to be a tough fight and we gave it our best."
East Coast GRC was created in 1997, when Bedok GRC was expanded to take in parts of Eunos, Marine Parade, Tampines, Changi and Aljunied. It has been contested four times so far, all by the WP.
In 2006, the PAP team won with 63.86 per cent of the vote. Its vote share dropped to 54.83 per cent in 2011, then went up to 60.73 per cent in the last general election in 2015.
The WP team ran a campaign championing diversity in Parliament and "a balanced system", among other issues.
The PAP team focused instead on issues such as jobs for residents and a new plan for East Coast.
Mr Heng also called on voters not to be "taken in" by opposition parties' claims of a wipe-out, given that the Non-Constituency MP scheme guarantees opposition voices in Parliament.
Dr Felix Tan, an associate lecturer at SIM Global Education, noted that Mr Heng's results showed that there is support for his leadership.
"After all, his team is facing a very strong opposition (team) from the WP. Plus, DPM Heng shifted to East Coast GRC at the last minute as well," he said.
National University of Singapore political scientist Bilveer Singh, who is an East Coast resident, added: "Mr Heng's coming here saved the constituency for the PAP. I think he will spend the next five years building it up."