Singapore Democratic Party (SDP) chief Chee Soon Juan yesterday asked voters to look at his party and what it had achieved and judge his credentials for themselves.
The party, he said, came up with a series of papers outlining alternative policies on issues from healthcare to housing and education.
"If we didn't dedicate our time to doing this, how do you think we were able to bring something like this up?" he said on a walkabout in Bukit Batok, where he is contesting the May 7 by-election.
He was responding to questions from reporters about remarks by Culture, Community and Youth Minister Grace Fu at a People's Action Party (PAP) rally on Friday.
She said that Dr Chee, who hoped to be a full-time MP, had not actually held a steady job.
The SDP, Dr Chee said in reply, is his "curriculum vitae".
He said a joke going around is that the SDP seems to be the PAP's "unpaid research arm", as some MPs are beginning to echo what the SDP has long argued.
He cited its minimum wage call, and said Singapore adopted the progressive wage model for certain sectors. While not a minimum wage, it is about the idea that wages of certain low-income workers "cannot be below a certain level".
He also said that such work was possible only because his time is dedicated fully to the party.
"It's all about priority. I can choose to be any one of them, sitting in their nice offices and earning the kind of salaries that they do," he said of PAP MPs, most of whom hold full-time jobs.
"But you make life's choices. I chose to serve Singapore, I chose to make sure we spend time talking about the issues.
"You just cannot sit in office and say: 'Hey, I'm doing my legal work, I'm doing my medical work'... and then when I'm free, I come down and I just shake a few hands, and then write a few letters for them on their behalf. That's not going to cut it."
Dr Chee said Singaporeans were used to this. But, "we want to be able to show them that full-time MPs from the SDP can take care of their needs a lot better than what you see in PAP constituencies".
He said he gets an income from writing books and selling them during elections: "Those tide me through the years in-between."
He was also asked to respond to comments by Prime Minister Lee Hsien Loong that there were racist comments referring to the PAP's Murali Pillai on Dr Chee's Facebook page, and that he had not refuted or removed them.
Dr Chee replied that the PAP should "stop playing politics".
"You can't pick and choose what comments are being made about," he said, adding that it was "not possible to go through" the hundreds of comments on his Facebook page.
"If the PAP wants to talk about racism, I refer you back to some of the comments the PAP leaders have made about the Malays - that's absolutely appalling."
He did not elaborate, but said: "They keep picking on things like comments on Facebook, when their party leaders are making racist comments themselves."
He also would not be drawn into responding to questions PM Lee raised yesterday about his character, saying he would respond later, after reading them.
But he said speakers at SDP rallies will no longer engage in personal attacks: "What we want to do is to be able to make sure we keep this kind of situation off the table... if it was done, we will make sure we put a stop to it."
He said the SDP prefers to focus its message on the fact that it is prepared to take over the town council, should it win, and will run it well.
"Our message continues to be to stay positive, not get into the kind of mudslinging that we all expected from the PAP side," he said.
The SDP has a rally tonight at Bukit Gombak Stadium from 7pm to 10pm.