The People's Action Party (PAP) manifesto for the upcoming polls on July 10 will be launched today by its secretary-general, Prime Minister Lee Hsien Loong.

The ruling party will also progressively introduce its line-up of candidates for the GRCs and SMCs in the next few days, said the PAP's second assistant secretary-general Chan Chun Sing yesterday.

He made the announcement at a virtual press conference to introduce the last eight of 27 new faces that will contest the election.

Unveiled over three days, the newcomers are a varied lot: 15 come from the private sector, including such fields as law, banking and business, while the remaining 12 are drawn from the public service, the social and non-profit sector, and the military.

Asked if any of them are of ministerial calibre, Mr Chan said it is "premature to do any such comparisons".

"Even for the 2011 and 2015 batches, it is premature for us to try to claim credit or success," he added, referring to the new PAP faces in the last two elections.

In 2011, when Mr Chan was introduced along with Deputy Prime Minister and Finance Minister Heng Swee Keat, Education Minister Ong Ye Kung, National Development Minister Lawrence Wong and Speaker of Parliament Tan Chuan-Jin, they were called the "Fantastic Five" - touted to be the core of the fourth-generation leadership.

Yesterday, Mr Chan told reporters that while he was at the new Ministry of Social and Family Development (MSF) from 2012 to 2015, many had asked him if he thought he had done well enough as a minister or done enough for vulnerable families.

But such policy work, he said, is a long-term project.

"Many of the children whom we are helping will take 15 or 20 years to grow up. We will never really know whether we have done well until, perhaps, 15 or 20 years later."

The same logic applies to other policies and issues, he added at the press conference streamed from the PAP headquarters in New Upper Changi Road.

"How we measure success is not whether they do well today or tomorrow only. It is whether they do well beyond the short term... And how do we collectively do well as a country."

As electoral candidates, the mindset to adopt is, "never be too anxious to claim success, but always be the first one to take responsibility to take Singapore forward", he said.

Mr Chan was also asked about criticism that the PAP candidates have similar backgrounds, resulting in the possible danger of groupthink in the party.

He pointed out that the entire slate of 93 candidates, including incumbents, come from diverse backgrounds in varied sectors, including business, social service and the public service.

"We have covered the various sectors, but more importantly, beyond just where they come from... we should avoid pigeon-holing people just because of (their) profession."

Every candidate, he said, has a unique personality, and Singaporeans will get a chance to know them better in the coming weeks.

On the lack of Indian candidates among the 27 newcomers, he said in the total slate of 93 candidates, there is an above-average representation of the Indian community.

There were nine Indian MPs from the PAP in the 13th Parliament, six of whom are office-holders, he noted.

This works out to 9.7 per cent of the total slate of PAP candidates, slightly higher than the ethnic composition in the population, as Indians made up 9 per cent of the resident population last year.

The need for all 93 candidates with different experiences to pull together as a team was reiterated by Mr Chan.

He said the PAP's leadership system is not one that involves pitting one batch of candidates against another.

"It is about different batches of people all coming together to serve with a common purpose."

Continuity, consistency and coherence underlie its policies and they are not done by an individual or a single batch of people.

"So that is how we will perform as a team for the good of Singapore".