Well before Dr Chee Soon Juan appeared at the promenade area beside UOB Plaza for his Singapore Democratic Party's (SDP) lunchtime rally yesterday, the crowd was prepped for his arrival.

Mr Bryan Lim, an SDP candidate for Marsiling-Yew Tee GRC, spent almost all of his speech explaining why he followed Dr Chee in politics despite the latter's various run-ins with the authorities and People's Action Party (PAP) politicians over many years.

He wanted people to know that Dr Chee was "humorous, resilient, sincere, intelligent and, most importantly, a patriotic person", and not as bad as the Singapore media had made him out to be.

"Dr Chee paid a heavy price for his political views. He lost his job and was made a bankrupt. He had many job opportunities overseas. He could have packed up and left for greener pastures. However, he turned them down because he has never given up on his political conviction," said Mr Lim, 38.

Dr Chee, who could not take part in the last two general elections because of his bankruptcy, is back in action this year, leading the SDP team in Holland-Bukit Timah GRC.

When he arrived at yesterday's venue near Boat Quay, he was greeted with a big roar from the crowd. He devoted a significant part of his 30-minute speech to his difficulties as a politician, the people who supported him and why he persisted.

"Through the years, my life has become an open book. Open for ridicule and attack by the PAP and their supporters," he said.

He also expressed gratitude to the "angels" who have bought his books and given him donations that have helped him get by. He revealed how a man once took a book and gave him a hongbao in a box of cupcakes. When he opened the red packet, there was a $10,000 note inside.

"Throughout my life, my political life, there have been angels that have blessed us with their compassion. Not always in terms of cash, but their deeds often give me the encouragement to go on with my work," he said.

Dr Chee made his political debut at the age of 30 when he contested in a Marine Parade by-election in 1992. The following year, he went on a hunger strike to protest against his sacking as an academic at the National University of Singapore, claiming it was politically motivated.

In 2001, he was sued for defamation by former prime ministers Goh Chok Tong and Lee Kuan Yew for remarks about an alleged loan to former Indonesian president Suharto. He lost, and that led to his bankruptcy which disqualified him from elections until 2012.

Dr Chee has also gone to jail for holding a rally and speaking in public without a permit. Now 53 and back in the running, his rally speeches have been circulated widely online, with many saying he is one of the best speakers in this election.

Dr Chee's teammates are medical professor Paul Tambyah, 50; compliance auditor Sidek Mallek, 55; and healthcare administrator Chong Wai Fung, 45.

In an interview with The Straits Times, he said sitting out the last two general elections helped make him a more effective leader, after being involved in the party's logistical preparations.

The way he conveys his ideas has changed as well. "My views on certain issues that we develop, we get better at them. They are more refined," he said. "And when we bring all these to voters, we can at least just be a bit more substantive, instead of just going on rhetoric and not being able to offer the voters concrete proposals."

The SDP, which has slowly shed its association with civil disobedience, is now foregrounding a host of alternative policy proposals on wide-ranging topics like income inequality, healthcare, housing and ministerial salaries.

They include removing the land cost from the prices of certain Housing Board flats, as well as allowing retirees to opt into receiving their Central Provident Fund (CPF) savings by instalments - an arrangement that is currently mandatory.

The SDP has also attracted a number of well-educated members in recent years, such as Prof Tambyah, former senior civil servant Tan Jee Say and psychiatrist Ang Yong Guan, although the latter two have left the party .

Dr Chee's image has also been softened by a short film made about his family life in a three-room Housing Board flat, and which has been circulating online as well. He said yesterday he did not pay for it to be made, but the filmmaker had shown up and volunteered to do it.

Asked if he had changed compared to his earlier years, the SDP chief chose to speak in general terms instead.

"We always develop," he told The Straits Times. "Somebody who tells you 'no, I don't change', is either somebody who is not very much in tune with their own self or not very cognisant of the fact that they need to constantly evolve."

The late Mr Lee once likened him to a "political gangster", but Dr Chee said he now notices more doors of the establishment opening to him. Last month's invitation from Yale-NUS College to a dialogue with more than 100 participants was "encouraging", he said.

"It's a natural progression of society opening up. And then with social media, people are beginning to understand what the SDP is about. And then they are beginning to become just a little bit more receptive to what we have to say and seeing what we've been trying to achieve."

Yesterday he told the crowd that part of his income is from the sale of his books and urged his audience to buy. When the rally ended, a long line formed as people waited to get his book and his autograph.

He told The Straits Times that he drew inspiration from the late opposition figure J. B. Jeyaretnam, a former leader of the Workers' Party who was also sued by PAP leaders for defamation.

"He stood against all odds," Dr Chee said. "He persevered."