Workers' Party (WP) chief Pritam Singh yesterday pushed back against suggestions that his party is just a "lite" version of the People's Action Party (PAP).
He said the claim made by Foreign Minister Vivian Balakrishnan during a televised debate was an electoral ploy.
Dr Balakrishnan had said during the debate that the WP manifesto outlined positions so similar to the PAP's that the ruling party could have written it.
Mr Singh, in response to questions during a walkabout in Kovan, said: "If that was the case, I hope the PAP takes up all our manifesto points and introduces them into their agenda, because that will really change the shape of Singapore, and we will have a more caring and compassionate society."
On Wednesday night, during an exchange with the WP's Sengkang GRC candidate Jamus Lim at the CNA debate, Dr Balakrishnan said: "It's almost a position where whatever line or stand the PAP has taken, you basically use that as your reference point and take a half step to the left."
Yesterday, Mr Singh, drawing a distinction between the parties, pointed to questions that the WP MPs had asked in Parliament about the corruption scandal involving Keppel Corp as well the fake news laws.
He said: "The proof of the pudding is in the eating. Did any PAP MP file any question on the Keppel Marine scandal? I think voters should think about that.
"Did any of them step up to consider the other alternatives to Bills like Pofma (Protection from Online Falsehoods and Manipulation Act)? I think these are the questions Singaporeans need to ask."
A key plank of the WP campaign for this election is the argument that checks and balances in Parliament are important, even in a time like this when Singapore is facing a crisis.
Mr Singh, alluding to the WP's motto of being a responsible and constructive opposition party, said that although Singaporeans want the opposition to scrutinise the PAP, they are "very discerning as to the type of opposition they want".
He said: "We've tried very hard to take that perspective on board and we have created a sort of culture within the party of an opposition that is credible.
"Not just locally but internationally as well, we're proud to stand as Singaporeans in spite of being the opposition."
When asked about the plaudits that Associate Professor Lim, an economics professor, received for his performance during the debate, Mr Singh said he "did credibly for the party", but that there was still a lot of work to do for the upcoming polls.
He added: "All our candidates have to work hard to serve people on the ground and in Parliament. It's more than just debates as well."
Mr Singh was also asked if the WP's Aljunied GRC team would take up any Non-Constituency MP (NCMP) spots if it loses at the polls. He said that it was too speculative to answer the question before election day.
While WP MPs have taken up the posts in the past, the party has always maintained that the scheme is a ploy by the PAP to dissuade Singaporeans from voting for the opposition.
Parliamentary seats are offered to the best performing opposition losers at the election under the NCMP scheme, which was expanded to provide for at least 12 seats.
Mr Singh said: "But people should think about it, why is the PAP so magnanimous in offering NCMP seats? It's something I hope all voters reflect on."
