SINGAPORE - On one side, there is the People's Action Party team helmed by Senior Minister Tharman Shanmugaratnam, who led his slate in 2015 to win the highest vote share of more than 79 per cent.

On the other is Singapore's newest political party on the block, Red Dot United (RDU), registered just two weeks ago and which had to scramble to find enough assenters to support its candidacy.

It may appear to be a typical Goliath versus David contest, but on Nomination Day, both sides made clear that no one is taking anything for granted.

In a speech at the nomination centre at Nan Hua High School, Mr Tharman, 63, said that his team is thankful for a contest.

"If we are elected, our first priority is to help our residents see through this crisis - anyone who's lost a job, anyone whose kids need looking after, anyone who has elderly parents who need care; helping residents see through the crisis," he said.

His team includes Senior Parliamentary Secretary for Trade and Industry and Foreign Affairs Tan Wu Meng, 45, and backbencher and lawyer Rahayu Mahzam, 39, who were both involved in the previous election. Joining them are newcomers Xie Yao Quan, 35, who is the head of healthcare redesign at Alexandra Hospital, and Shawn Huang, 37, a director for enterprise development at Temasek International.

The RDU candidates form the only team that the party is fielding this election.

It will see the return of three candidates who had stood in previous elections: Mr Ravi Philemon, 52, the managing partner of a media company, and educator and counsellor Michelle Lee, 43, as well as theatre director Alec Tok Kim Yam, 55. The first two were previously Progress Singapore Party members, while Mr Tok was from the Singapore Democratic Party.

They will be campaigning with entrepreneur and author Liyana Dhamirah, 33, and legal engineer Nicholas Tang, 28, who are both competing in an election for the first time.

RDU was registered as a political party on June 15 after submitting its application on May 26.

In her speech, Ms Lee said that "it is well known that SM Tharman is the most well-known politician in Singapore, respected across everyone in the political spectrum. Jurong also had the highest percentage of votes in the last GE".

"RDU thought long and hard but we feel that GE is about more than one person and one party, it's about people of Singapore having the choice of more than one party. Courage is not about the absence of fear, it's about doing the right thing despite the odds."

The PAP slate for Jurong GRC has been the subject of attention over the past weeks, after a candidate that the party had intended to field, Mr Ivan Lim, withdrew his candidacy. Mr Tharman introduced Mr Xie on Monday to replace him.

Before that, Dr Tan was embroiled in a controversy for an article he had penned that criticised Workers' Party chief Pritam Singh for supporting Singapore playwright Alfian Sa'at, saying Mr Alfian is not a "loving critic" of Singapore.

Asked if the two episodes will affect the PAP team's standing with voters, Ms Rahayu told reporters: "I think we have to be realistic. A lot of things happen in an election and events like this will clearly cause some erosion of faith in our team. But what we hope is that residents will also give us an opportunity and also look at all the efforts that we've done."

The PAP and the RDU will be fighting for the support of 131,234 voters in Jurong GRC when voters go to the polls on July 10.

The nine-day campaign period starts immediately.